The salary cap pretty much killed big, multi-player blockbuster deals. Now teams can't afford to take additional players that may have "throw-ins" like with the Lindross (Que/Phil) deal because they all count against the cap. The younger, cost-controlled player is now what teams are looking for as far as additional players in any deal. If you're lucky enough to have a couple 2nd/3rd liners who can play regularly and contribute on entry-level deals then that makes fitting your superstars and the rest of the team in under the cap way easier.
If Det and TB were serious at trading players I would have to think that TB would want Mantha and another top prospect (AA, Svech) for Drouin though as his ceiling is supposed to be higher than Mantha's is. As for Stamkos, he would be nice to have, but at what price does he make sense for the Wings? 10mil is way too high and would mean we would have to cut salary somewhere else.
What's the deal with Franzen's salary? Why don't they just move him to LTIR so that his salary doesn't count against the cap? If we had relief from Franzen's hit and traded Jimmy then we would have TONS of money to go after a true #1 D and get some scoring help up front!