Welcome to the NHL off-season, Penguins and Sharks fans. The rest of us have been here for weeks, and in some cases months. It’s been pretty slow, to be honest. But now that everyone’s arrived, we can finally kick this thing into high gear.

So what will the summer hold? Nobody knows, but as with most things in life, we can find some clues in what’s come before. After all, the NHL tends to be a copycat league where new fads can take hold quickly and teams can sometimes change direction on a dime. One year’s surprise might end up foreshadowing the next year’s must-have trend.

Let’s prepare for the future by looking back at the past. Here’s a look back at a half-dozen of the biggest stories from the 2015 off-season, and what they could teach us about what to expect this year.

The story: The Phil Kessel deal. In arguably the biggest trade of the off-season, the Penguins sent a first round pick, a prospect and some smaller parts to the Maple Leafs for Kessel, with Toronto retaining a chunk of his salary. It was a deal that had been rumoured for weeks, and it saw the two teams make clear their intentions for the coming season: the teardown was on in Toronto, while the Penguins were all-in on a Stanley Cup run.

The lesson: Sometimes, bold trades really do work out.

We all know how this ended for the Penguins, with the vision of Kessel skating the Stanley Cup around the rink in San Jose still fresh in our memories. The trade looked dicey as Pittsburgh tumbled off to a rough start, and even as the team turned around, Kessel’s numbers never approached the sky-high expectations the deal created. But he found his groove in the playoffs, leading the team in scoring and even earning some Conn Smythe Trophy love.

While the deal was a major win for the Penguins, it worked out for Toronto too. None of the pieces it acquired in the trade had much impact during the season, but the Leafs cleared cap room and added depth to their prospect pipeline. And maybe more importantly, Kessel’s absence helped contribute to a last place finish that will yield Auston Matthews next week. One year in, the Kessel trade looks like one of those deals where both teams won.

Who it could impact: Any GM who’s still trotting out the “You just can’t trade in today’s NHL” line. Fans have been hearing that for years, from various GMs around the league. And it’s undoubtedly true that making trades is more difficult under a cap system; just look at the first few months of this season, where we didn’t see a single deal involving an NHL player until mid-December.

But as Jim Rutherford went out and proved, difficult doesn’t mean impossible. Between the Kessel deal and other trades for Nick Bonino, Carl Hagelin, Travor Daley and Justin Schultz, the veteran GM helped turn the Penguins from a top-heavy pretender into a well-balanced contender. Fans in other cities who are used to being serenaded with excuses from risk-adverse GMs may want to take note.

The story: Offer sheet worries lead to big trades. Dougie Hamilton and Brandon Saad both went from young franchise cornerstones to trade bait within days of the draft, with Hamilton heading from Boston to Calgary and Saad going from Chicago to Columbus. In both cases, the deals were inspired at least partly by fear that the players, who were both RFAs, could be offer sheet targets.

The lesson: NHL GMs hate having their hands forced, and would rather trade a player on their own terms than risk the threat of losing a player to an offer sheet.

The irony, of course, is that that tends to be all an offer sheet ever is: a threat. It’s been over three years since one was actually signed (Ryan O’Reilly, which almost led to disaster for Calgary), and almost nine since one actually worked (Dustin Penner, which almost led to a barn fight).

And yet, GMs apparently still worry about falling victim to one. In theory, that’s the sort of thing a team could use to their advantage.

Who it could impact: The list of this summer’s RFAs features some decent names, including Nikita Kucherov, Seth Jones, Nathan MacKinnon and Jacob Trouba. It’s hard to imagine any of those guys switching teams this summer. Then again, we could have said the same for Hamilton and Saad around this time last year, and we saw how that worked out. At the very least, don’t be surprised if some sneaky front offices find a way to float a few rumors over the coming weeks.

The story: All those goalie trades. The days around the entry draft saw a flurry of trades involving goaltenders, with Martin Jones, Cam Talbot, Eddie Lack, Robin Lehner and Antti Niemi on the move.

The lesson: Goalies are always available on the market, and you can turn your season around with the right one. The Sharks raised a few eyebrows by acquiring Jones, but the last time we saw him he was standing on his head in the Stanley Cup Final.

Of course, you have to find the right fit. The Stars gambled on Niemi, figuring that they could pair him with Kari Lehtonen to form an expensive but effective veteran pairing. That didn’t work out, and may have cost the Stars a legitimate chance at a Stanley Cup run. Other teams also paid for missing out completely once the dust had settled; the Flames didn’t upgrade the position, and paid for it during a frustrating season.

Who it could impact: A handful of teams will be looking for goaltending again this summer, with the Stars and Flames likely leading the way. And there could be plenty of sellers with a new Las Vegas team now all but a sure thing for 2017. Teams with two goaltenders know that they’ll risk losing one in next year’s expansion draft. Some of those teams might find themselves wondering if it makes more sense to get something back in a trade now, rather than lose an asset for nothing in a year. That could be good news for teams looking to upgrade, and should lead to another busy off-season at the game’s most important position.

The story: The Sabres load up. In addition to trading for Lehner, the Sabres also pulled off a blockbuster trade for Ryan O’Reilly. That was in addition to hiring coach Dan Bylsma (after almost landing Mike Babcock), and of course drafting Jack Eichel with the second overall pick.

The result was a league best 27-point improvement. Granted, that still wasn’t enough to get them into the playoff race, given how big a hole they were starting from. But it was still an impressive step forward, one that may position the Sabres for playoff contention as soon as this coming season.

The lesson: Rebuilds can’t last forever. Tim Murray was always very clear about having a plan, and that plan was going to involve some pain. But he also seemed to understand that a rebuild can’t be a perpetual process. You can gun the engine and spin the wheels all you want, but eventually you need to shift into drive. Murray and the Sabres chose last summer to do it, and for the most part it worked.

Who it could impact: In a league where top draft picks are more valuable than ever before, there’s no shortage of teams that are rebuilding. The question is which ones, if any, decide to try for a Sabres-like move forward this summer.

It’s may still be too early for the Maple Leafs, although Steven Stamkos will be tempting, and teams like the Canucks and Avalanche don’t seem to realize they’re rebuilding yet. But the Jets have enough young assets that they could get aggressive. And the Coyotes already improved last year, and could be well-positioned to push even further under a new front office. The Blue Jackets situation is dicier, but patience could be running out in Columbus. And of course there’s the Oilers, the poster child for perpetual rebuilds; basic probability suggest that they have to find some traction eventually.

The idea here isn’t that one of those teams will see a 27-point gain. But don’t be shocked if one or more end up being more aggressive than expected over the summer, and if that aggression isn’t just about stockpiling draft picks and prospects.

The story: The rise of the rookie coaches. Last year, seven NHL teams headed into the off-season looking for new coaches. And while experienced names like Babcock, Bylsma and Todd McLellan were snapped up fairly quickly, three teams ended up turning to rookies with no NHL head coaching experience: the Red Wings (Jeff Blashill), the Devils (John Hynes) and the Flyers (Dave Hakstol).

Blashill’s hiring was expected, and he delivered another playoff season in Detroit. But Hynes and (especially) Hakstol were lesser known names, and both exceeded expectations in their first years behind the bench. Hynes took a Devils team that most had pegged as a contender for last place and kept them in the playoff race for most of the season, while Hakstol earned a post-season berth with the rebuilding Flyers.

The lesson: When it comes to coaching, you don’t always need to recycle the same old names over and… oh, hey there, Ducks fans. Didn’t see you guys. Huh. Well, this is awkward.

Who it could impact: With the Ducks having settled on Randy Carlyle, that leaves the Flames with the only coaching vacancy, one that will reportedly be filled as soon as Thursday. So far, all of this year’s hires have been coaching veterans, and that includes the weird Blues situation that saw them already name their new coach for next season. If rumoured favourite Glen Gulutzan ends up being the pick in Calgary, that would leave guys like Travis Green on the outside looking in.

The story: Sanity reigns. After years of seeing short-sighted NHL GMs torpedo their teams with indefensible free agent signings and ill-advised trades, last year’s off-season was dominated by a relatively novel factor: common sense. Nobody got too crazy throwing money around, and while some GMs received better marks for their work than others, nobody went into full-on panic mode. That may explain why only one GM was fired in the year since (two more left the job but remained with their organization).

The lesson: It can be done. And apparently even the most desperate NHL GMs are capable of learning from their past mistakes.

Who it could impact: All of us, if the GMs keep this up. Come on guys, we’ve all got a long summer ahead of us, and we’re relying on you to make it interesting. Bring the crazy, early and often. Hockey fans are counting on you.