In the end, this is the summer to make a trade for a dman. Players will be available due to expansion draft next summer. Teams will be looking to get something for their players while they can. Trouba is the perfect target.
If you think this class is weak, wait until next year. Lots of 35+ players contracts expiring and not much else. Hedman will be a UFA next year, but I can't imagine he'll make it that far especially if Stamkos does leave TB.
In today's NHL, who would be willing to part with a top pairing defenseman? I agree that we need a stud d-man, but who are you thinking about getting that anyone would be willing to part with? PK Subban? Shea Weber? Ryan Suter? Kris Letang? Alex Pieterangelo? Drew Doughty? Erik Karlsson? Those are some of the best in the league right now and I can't imagine any of them moving even if we offered Dylan Larkin. Even if we were able to swing a deal for one of those guys or some other top tier d-man, that's not really going to fix the problem. The unit as a whole isn't very good. The UFA defensemen aren't great, but they're better than what we currently have and I think several minor upgrades would be in our best interest considering the unavailability of top tier d-men around the league.
Trouba might be available. The Jets have 3 defensemen with a nmc, they'll either have to expose Trouba or only protect 4 forwards as it stands now, assuming the PA gets their way and players with a nmc have to be protected. Unless they make a deal with the expansion team(s) they'd lose someone they really don't want to lose. Trading Trouba or convincing one of the others to waive their clause is their best option.
This year is weaker than years previous, and next year and so on will be weaker again, that's the way the NHL is going. Teams are locking up their stars, so not near as many hit the open market, hence the importance of drafting and developing...
I've stated my opinion on this so many times now, but here it is again. Like you said, we're not getting any of the top "current" defensemen, aka Doughty, Weber, Pietrangelo, etc. The key is looking for young, up and coming defenders, that you think have a chance to develop into the next wave of elite defensemen. Who that is? I'm not sure, but they're out there.
I want us to go hard after Jacob Trouba, not because I think he is an elite defenseman, but because I think he has all the tools and potential to become an elite defenseman in a few years. I also think he is better than the majority of what we have on our blueline right now, and even if he doesn't hit his ceiling, he will still be a very solid second pairing defenseman. So we can go after a Keith Yandle and pay him $6+M to be our second pair defenseman, basically a left handed Mike Green, or we can package together a deal that could bring Jacob Trouba in with a floor of second pair defenseman and ceiling of elite top pair defenseman...
Abby has taken more of a vocal role with the media. He also seems to be more of a locker room voice as he matures. I think he gets the next A. Larkin will get one eventually unless he is just a flash-in-the-pan, which I doubt will be the case. He certainly looks like the real deal. I hope his locker is next to Z's like Z's was next to Stevie's back in the day.