Sometimes nostalgia arrives before its time. You’re driving along the Nimitz, passing the Coliseum and picturing an empty, barren landscape that might someday house a bunch of housing projects or business offices. Warriors, Raiders, A’s — all gone.

It’s a curiosity, though, how the Coliseum site comes into play as the A’s set their plans for a new ballpark. Not so long ago, most everyone assumed it was a terrible idea. You wonder, just now, if it’s the best alternative.

Consider the simple matter of timing. The Raiders’ lease guarantees them a Coliseum home field only through next season, and they’re due to open shop in Las Vegas in 2020. The NFL would love to see them play out the string at Levi’s Stadium, or even at Cal. If the Coliseum were ready for demolition in early 2019, it’s conceivable the A’s could have their ballpark built there by 2021. And there wouldn’t be the slightest doubt about the blueprint: full steam ahead, no complications, convenient BART station, easy parking.

How do you think fans would feel if the A’s chose Howard Terminal, or the Lake Merritt site (near Laney College), without a concrete promise as to when it actually opens? Most forecasts estimate at least a five-year wait in each case. In the A’s current climate, a swirl of distrust among fans grown tired of disheartening trades and “small-market” excuses, that wouldn’t generate much excitement.

According to a number of reliable sources, the A’s have ruled out Howard Terminal. Let’s hope so; It’s just too grim. As an active port, this is a fully industrial, no-charm area with live train tracks across the Embarcadero (imagine alcohol-sodden fans playing “beat the locomotive”) and the nearest BART station (12th and Broadway) about a mile away. It’s a windblown weather pocket that, some say, calls up the memory of Candlestick Park. The only thing in its favor, one would surmise, is that there wouldn’t be any local residents or merchants to displace.

“I think Howard is terminal,” said Andy Dolich, the former A’s executive and perhaps the most authoritative local voice on sports-marketing issues, in a phone conversation Saturday. “It’s just incredibly fraught with complex infrastructure issues, like a PG&E plant that would have to be removed. The parking could be a mess. Too far from BART. Dealing with federal, state, regional and local agencies that need satisfaction. And who knows what seismic studies would show about levels of toxicity below the ground? And who pays for all that? (A’s president) Dave Kaval has said the ballpark will be privately financed. But what does that really mean?”

The Lake Merritt site, said to be the A’s favored location, got a recent boost when Jowel Laguerre, chancellor of the Peralta Community College District, switched his stance and sounded enthusiastic about sharing that property with the A’s. It would mean jobs and internships for Laney College students, and only the Peralta District offices would have to move. It could take years, though, to satisfy the interests of people who would be forced out of their homes or local businesses. And the traffic? Don’t ask.

“I’m not sure how they figure that out,” said Dolich. “We’re not at the point where everybody’s gonna take BART (a 5 to 10-minute walk). If you look at the renderings, the park sits right on 880. Laney’s got about 9,000 students, most of them commuting, and that’ll be fun. Hey, no traffic on 880 Monday through Friday, right? You also have an estuary stream that’s right on the property, an active point for wildlife, which means environmental studies and a lot of push-back. I’d say to be optimistic, you’re waiting at least five years there. You’d really have no idea when they’d actually put shovels into the ground.”

Settling for the tired, ancient Coliseum site wouldn’t be such a bad thing. Build a 35,000-seat ballpark with pristine views of the Oakland hills — a staple of the A’s park before Mount Davis ruined everything — and let your imagination take it from there.

“Go back 18 years or so, and see if anyone really thought China Basin was a great place to hang out,” said Dolich. “It seemed like one of the worst sites for the Giants. And look where we are now. Go across the bridge, and the (Coliseum) footprint is Rodeo Drive compared to China Basin back then. Build a ballpark that doesn’t resemble San Francisco in any way. Oakland is cool, it has a vibe, it’s definitely attracting a younger demographic who can afford to live there. Capture that Oaktown vibe, so when you go into the ballpark, there’s no question where you are.”

Whenever the A’s choose to disclose their decision, it would help immeasurably if owner John Fisher actually attends the news conference (which he did not during the major executive transition, leaving Kaval to explain his new position). Let’s hear some concrete promises about timing and some enthusiasm about spending big money on the future. Not from Kaval or Billy Beane, but the man who owns the team — and needs so badly to gain the fans’ trust.

I can’t help but be skeptical, because that’s the atmosphere Fisher has created. I’m also an optimist at heart and not given to premature nostalgia. In time, a nice little village could be built around the Coliseum site, bringing the A’s right up to date. Sometimes the most simple solution is the best.

Bruce Jenkins is a San Francisco Chronicle columnist. Email: bjenkins@sfchronicle.com Twitter @Bruce_Jenkins1