There's some common ground for a modest Sabres-Wings trade that doesn't include Cozens or Byram or anyone with an NTC who might nix a trade to either team. Rasmussen, Lyon, Berggren, Veleno are all possibles for the Sabres. Samuelsson, Peterka and perhaps Quinn would be of interest to Wings. A Wings D prospect (Wallinder/Buium) or AlJo for a Sabres F prospect (Rosen/Ostlund) is also not far off a decent match.
Looking down the Buffalo roster, they seem to be shy on some veteran RHD (and in the farm) and LH centers and are a quite young group overall. Seeing as both Ras and JV have played center and all over the lineup, they could be of interest to Buffalo with Greenway on the LTIR, as Ras has size and JV will actually hit and is not exactly small.
As I understand the NTC, they now have to be registered with NHL HQ, so the players cannot pick the teams on the fly. Trouba would have been unique, as he was just putting his together, but the resident Wings should have theirs firmly in place.
I can see Buffalo moving on from one younger LHD (Bryam or Samuelson) as 4 higher priced LHD on the roster is not optimal unless one of them is natural on their off side (it does happen) for one of JV/Ras plus maybe an Al-Jo, the other off the wall one I could see would be Holl to add some veteran presence for a couple of seasons as 3RD for the Sabres.
I think the only way SY move on from Lyon this year is when they toss in the towel on the season, and I doubt the Sabres will be the landing spot at the TDL.
Like you, I only see modest things as SY will want his chosen roster top perform, the new coach should unlock things a little, so anything that happens will most likely be a swap of underperforming pieces that hopefully a new team gives them new life.
Neither team is truly out of it yet, the last WC spot is currently the Sens at 4 games over 0.500 with a lot of games to play, so you never know, maybe a bigger swap is in play.