--All of the following assumes that the Isles hire Lou Lamoriello.--
Carolina has recently indicated that they are open for business in the trade market, and have said they will seriously listen to offers for the 2nd overall pick. Given their wealth of defensive talent, I would guess they are open to trading Faulk. Svechnikov is almost the guaranteed 2nd overall pick. It's also well known that Carolina mainly lacks offense. So essentially, the Canes trade Faulk and Svechnikov for Lee (40 goal scorer), the RFA rights to Nelson (frequent 20 goal scorer screaming for a change in scenery), Aho (very young, promising defenseman with NHL experience), and a wealth of picks (I assume future Top 6 2 Way Forward Joe Veleno, future top 6 winger-center Kotkaniemi and physical right shooting defenseman Alexeyev). I think this trade is slanted in Carolina's favor, but hey, that's how it works when you trade into the Top 3 of a draft.
It appears that Buffalo is looking to move on from Lehner, but not without getting something in return. A 2nd and a middling LHD prospect should be enough for his rights. If Buffalo wants Greiss, they can have him. In that case, the goalie pairing would be Lehner-Soderstrom. If Buffalo doesn't want Greiss (they always do okay in Free Agency, you'd think they could do better than Greiss), the goalie pairing would be Lehner-Greiss. Sure, Lehner isn't an elite goaltender by any means, but he's already used to being a full time starter. After years of having a 1a-1b goalie situation, maybe the Isles should return to a clear starter-backup format of goaltending.
The new first line would miss Lee's scoring touch, but Svechnikov would be an immediate Calder candidate next to Tavares, and will grow into a better all around player than Lee. The second line last year was spectacular, and I have no desire to change it. The third line will finally have an identity as a scoring line rather than being the leftovers. Bellows and Ho-Sang are both exciting young players, and could do some real damage to teams after they've been exhausted by the top two lines. Filppula brings a veteran true-center presence to that line. Call it a hunch, but I have a strong feeling this is Koivula's year. As physical as he is, he brings enough of a scoring touch to bring a diverse threat. I think he'd revolutionie the 4th line and bring the best 4th line in hockey back to its glory days.
Adding Faulk to the top pairing would immediately make our defense worlds better. Given Leddy's lack of a steady partner last year, if we can keep Faulk healthy, I could see a nice rebound year for Leddy. Nobody seems to be talking about how good of a season Hickey had last year. His scoring and +/- improved greatly, so rather than letting him walk, I see the Isles handing him a brief "prove-it" contract to see if there was more to last season. Pulock had a solid rookie season, showing the team he's ready for Top 4 duties. I see no reason not to give him a comfortable spot on the middle pairing. While I'm not over the moon about a Pelech-Boychuk bottom pairing, I'd say it's well balanced and far better than the circus we had last year at the bottom pairing. All in all, I think adding Faulk allows the rest of the defense to work with minutes more appropriate to their age and skill.
In terms of salary cap concerns down the road, Ladd's and Boychuk's NMC/NTC situations relax next offseason. We will be able to ask for "no-trade-lists" instead of being outright unable to move them without their say so. Look for the Isles to sacrifice picks next offseason to move one or both of their contracts. Maybe Seattle enters the league and the Isles pull a Grabovski? Who knows. Either way, there will be ways to make room for Barzal's and Beauvillier's contracts down the road.