Banner and Hulk are highly appreciated but often given more muscular and/or thinner body types than they're supposed to have, in order to make them more conventionally attractive. Banner (as played by the so sexy Ruffalo) is the chubbier a guy is allowed to be in fandom in order to be sexualized.
Timothy Dum-Dum Dugan, vintage daddy with one hell of a mustache from Captain America: The First Avenger. The 'stache and talking makes him appear like a caricature of typical pre-War strongmen from circuses, and these guys were all but thin.
Heimdall technically doesn't look like that (Idris Elba is kinda built like a Greek statue!), but he's got such a daddy feel I couldn't help imagining that under his big armor is something cuddly and powerful.
Poor Volstagg, he's the only one of the Warriors Three to simply never be sexualized --maybe would it help if they had actually casted a fat actor to play him, instead of the Russian gay mafia guy from Dexter.
Jasper Sitwell is almost a cub, in his suits and ties he doesn't really give a strong bear impression, but when Maximiliano Hernandez posts bearded selfies on his Twitter I just melt. I don't know if Sitwell is HYDRA or not but it was funnier this way.
The ultimate muscle bear from Guardians of the Galaxy. I don't know who's more endearing, Drax or real life Batista.
And Happy Hogan from the Iron Man series because everybody likes bodyguards who can double as business pigs.