Well I'd like to see Namor, Torch, and Union Jack (I wouldn't count Bucky in the poll because he's more than JUST one of the Invaders, and should be part of the movie even if the rest WEREN'T included). Sadly, Namor might be part of the Fantastic Four rights, in which case forget it, cause FOX ain't doin' anybody any favors. But then again, Universal had the rights to Sub-Mariner a while back and if THAT'S still the case maybe Marvel could arrange some kind of deal. OR, for all we officially know, maybe Marvel has the rights at this point and they're just not tipping their hand too early.
As for the Torch, I'm sure Marvel's rights to him are secure, what with him being a different character than the FF Torch, but given that he's still the same powers and name, it wouldn't surprise me if FOX TRIED some kind of legal action. Just look at the debacle over the "Watchmen" movie. FOX KNEW the whole time that Warner was making the movie, NEVER asked them to cease and desist, and then once the film was shot and ready for release they took 'em to court, strongarming them into either settling or having to delay the release of a project they'd poured millions into. I could totally see them TRYING something similar with Captain America over the Torch issue. Even though they wouldn't really have a case, because they're not the same characters, IF they timed such a legal complaint close enough to the release date they might have pressure on Marvel to settle, rather than Marvel taking the time to delay the release and go to court and PROVE their rights. And if little ol' me, just another fanboy, has thought of this possibility, I can GUARANTEE that Marvel has considered it too, and might just as soon not include the Torch at all rather than risk possible trouble over it. Probably the best option for including him would be an idea I've heard mentioned about just calling him "Toro", and not including the actual Toro character(who would be redundant anyway, especially in a movie with so many characters already).
IF they don't have Namor and the Torch I'd go with just Union Jack, and Destroyer(make him a part of the French resistance or something) and maybe a non-powered Spitfire.