A gaping white trumpet flares open at the bottom of the escalator at Liverpool Street station, ready to suck commuters into another dimension. The smooth concrete panels splay out to meet walls of faceted, enamelled steel, beneath a roof that zig-zags back and forth in angular waves, as if the whole space has been disturbed by whatever force lies beyond the great portal.

It is a fittingly momentous entrance, given that this dilated Anish Kapoor-style orifice leads to the parallel universe of Crossrail. Deep below the streets of London, the £15.4bn infrastructure project has burrowed out a world of vast streamlined passages and immensely long platforms lit by digital displays, promising to whisk you from the City to Paddington in 10 minutes, or to the towers of Canary Wharf in just six.

It is a new route not only for people but for flows of finance, an aquifer that is irrigating abundant crops of speculative property development along its 73-mile journey from Reading on its west tip to Shenfield and Abbey Wood on its east. It will increase London’s transport capacity by 10%, and is predicted to increase surrounding property values by more than 30%. With the first trains of the Elizabeth line set to start rolling in December, before the full route opens next year, how is the architecture of this great nourishing artery shaping up?

Facebook Twitter Pinterest Floundering across the tracks like a beached whale … Abbey Wood station. Photograph: Oliver Wainwright

Wandering the cavernous passages of the central London stations for the first time, it is hard not to feel awed by the sheer size of it all. The trains will be 200 metres long, carrying up to 1,500 passengers – almost twice as many as an existing tube train – and the stations have been scaled up accordingly. Some, like Bond Street, are so big that their entrances bookend virtually an entire district. Reaching the trains entails being funnelled through pristine white passages, their walls stripped of the usual clutter of advertising, like the eerie corridors of Stanley Kubrick’s spaceship in 2001: A Space Odyssey.

At the platforms you find a full-height wall of glass doors, with bands of digital displays, vents, speakers and a long ribbon of light, every function cleverly contained in one continuous surface that separates passengers from the tracks. No longer will you have to crane your neck to see the departure screen behind a dangling sign: there’s a live display above every door. It is a model of elegant efficiency, a galaxy apart from the creaking, sooty state of much of the 150-year-old London underground network, yet with familiar touches that make it feel like part of the same family.

The urge to banish clutter makes it slick and precise – but you feel like you're trapped in a computer simulation

“We’ve looked back to go forward,” says Julian Robinson, Crossrail’s head of architecture, who cut his teeth on the Jubilee line extension as a junior architect in the early 90s and knows every inch of the tube. His team drew inspiration from the work of Charles Holden and Frank Pick in the 1930s, a golden age of London transport design that saw stations such as the flying saucer pavilion built at Southgate. Its uplighting columns inspired the freestanding “totems” that punctuate Crossrail’s passages, holding signage, speakers and CCTV, freeing the walls from the usual jumble of bolted-on bits.

Elsewhere, the raw logic of the engineering has provided the aesthetic steer. The streamlined form of the intersecting corridors comes from the amorphous geometry of the sprayed-concrete tunnel lining, a different technique from the usual iron or concrete retaining rings that form right-angled corners, familiar to the rest of the underground. The smooth bends are helpful for crowd flow, something the designers have encouraged with sinuous lines between the concrete panels, creating “fast spaces” in the passages and “slow spaces” on the platforms, a psychological trick enhanced by cold and warm lighting.

Facebook Twitter Pinterest Salute to Soho … the black terrazzo with gold touches at Tottenham Court Road station is a nod to the area’s glitzy night-time economy. Photograph: Crossrail

It is all impressively slick and precise, but the urge to banish clutter makes the platforms rather monotonous, sterile places. The relentless grid evokes being trapped in a computer model, and there’s none of the quirky character of some of the existing tube stops. The Technicolor Paolozzi mosaics of the Central line at Tottenham Court Road (a chunk of which were controversially removed by Crossrail works), or the deep indigo tiles of North Greenwich, make those stations easily identifiable at speed from a crowded carriage. The central stops on the Elizabeth line will be a continuous blur of beige.

“There’s a tension between the line identity and the station identity,” admits Robinson, who says that the overarching idea was for the line-wide experience to be consistent, while the stations responded to their local context at street level. The western entrance to Tottenham Court Road station, designed by Hawkins Brown, is a dark place of black terrazzo with gold touches, in reference to the glitzy night-time economy of Soho. The concrete ceiling of Farringdon station, by Aedas, has a diamond-shaped structure, in a nod to the jewellers of Hatton Garden. The entrance to Woolwich, by Weston Williamson, features panels of bronze cladding in homage to the area’s former gun foundries. It looks in need of artillery, cowering at the foot of the new Berkeley Homes towers.

Compared with the fluid drama of the tunnels, the stations all feel a bit meek as they surface. Rather than straining to be “contextual” with naff local allusions, why not deploy a strong Crossrail identity at street level – like the classic oxblood-red tiles of Leslie Green’s Piccadilly line stations built at the turn of the 20th century – and then vary the treatment on the platforms, so passengers know where they are from a glance through the window?

Facebook Twitter Pinterest Blue sky thinking … the cloud artwork at Paddington station. Photograph: Crossrail Ltd

The answer, as ever, can be found in the project’s cumbersome procurement process. While the Jubilee line extension, hailed for its architectural ambition, gave each architect responsibility for an entire station from entrance to platform, the scale and complexity of Crossrail led duties to be divided. The swooping white kit of standardised line-wide components was designed by Grimshaw Architects and engineering giant Atkins, while separate contractor-led teams were selected for the individual stations’ ticket halls and street frontages, styled by a range of safe corporate firms, and mostly designed with a larger commercial building on top.

Much of it is polite background architecture, with a tendency to make the extraordinary feel ordinary. Robinson’s tenets of exposed concrete elements and “self-finish” materials gives many of the stations a pleasingly raw heft, with square-coffered and origami-like folded ceilings, variously ribbed and moulded. But there is little of the oomph that you might expect from the grand scale of engineering, nothing like the atmospheric descent into Westminster station or the plunging blue glass wall of Southwark.

Paddington offers a brief moment of wonder. A 90m-long void has been sliced into the street next to the Grade I-listed train shed, where escalators plunge down past gigantic concrete columns. In a first for the underground network, passengers will be able to stand on the platform and still see daylight 30m above. The scheme was originally designed by Will Alsop in the 90s, then taken over by John McAslan, and finally executed by Weston Williamson. The dilution is evident. To add some sparkle, the entrance has been topped with a huge glass canopy, etched with a cloud pattern by Spencer Finch, in one of the many artworks that adorn the line. Yayoi Kusama is installing some loops of polished steel balls outside Liverpool Street, while Conrad Shawcross is bringing one of his trademark bronze spirals. It’s hard not to think that the artistic effort would have been better invested in the architecture of the stations themselves.

Facebook Twitter Pinterest Sparkling ideas … Farringdon station, which references the nearby jewellers of Hatton Garden. Photograph: Simon Periton

There was a moment, much earlier in the process, when the architects had a licence to dream more freely. Designs in the early 90s, by Ralph Erskine and BDP, depict cathedral-like spaces underground, reached by dramatic winding ramps. The entrance to Tottenham Court Road station was planned to take the form of a huge void in the shape of a beehive, plunging down from the middle of Soho Square, like the rotunda of New York’s Guggenheim museum, topped with glazed domes. Plans were delayed by economic recession and, by the time the Crossrail route was finally enacted by parliament in 2008, the tide had turned against such ambitious (and costly) ideas. The age of the icon was in decline.

As the line moves further east, some architects nonetheless appear to have been given a looser rein, with mixed results. Whitechapel, still far from complete, will see an undulating green-roofed bridge by BDP, thankfully mostly hidden behind a retained Victorian facade. Norman Foster has made a big inflatable tubular greenhouse at Canary Wharf, but the station itself, by Adamson Associates, takes a less inspiring form than its rooftop jungle promises. At Abbey Wood, near the Thamesmead estate, Fereday Pollard has conjured a timber-framed, zinc-topped manta ray. Its airy ticket hall is a breath of fresh air, although from the outside it is unbearably clunky, floundering across the tracks like a beached whale.

Ilford is to receive a gigantic grey-and-glass box that has all the finesse of an out-of-town storage depot

Beyond Whitechapel to the east and Paddington the the west, the route becomes the realm of Network Rail, over which Robinson’s team had little influence. The difference is profound. Ilford is to receive a gigantic grey-and-glass box, courtesy of Atkins, styled with all the finesse of an out-of-town storage depot. Ealing Broadway won’t fare much better, with a big canopy designed in the retail park vernacular by Bennetts Associates. Other outer London stations are set to be adorned with a similar assortment of canopies and boxes, along with occasional public space improvements to soften the blow. It speaks less of a magnificent new east-west link than the clutter of business-as-usual network improvements, a coughed hymn to value engineering.

Transport bosses moan of the constraints on the total budget (already exceeded by £600m, it was recently announced) but some joined-up design thinking across the entire route could have lessened the feeling of a two-tier line. An opportunity to capture the value of this huge public investment was sorely missed. A recent report estimated that the total uplift in property values across the line could be as much as £10.6bn by 2021, soaring to £20.1bn by 2026, nearly a fourfold increase in the original estimates – all being siphoned into the pockets of private landowners.

The Elizabeth line is an impressive achievement for sure, but with plans for Crossrail 2 now gathering momentum, there are some crucial lessons to be learned.