as some here may know, i am a big fan of comics.
i think chris evans is, was and always shall be johnny storm. he was a great fit for that role.
i do not believe he is a good fit for captain america at all - captain america has always been the square jawed leader of men.
chris evans plays a good funny come action guy, nothing more. he is not a leader of men, could you see him ordering tony stark ( robert downey's character) around never mind thor ! hahaha no !
marvel have gotten some perfect castings though i.e. blade, iron man, johnny storm, dr doom, xavier, beast, mystique, magneto, bruce banner ( norton), deadpool, sabertooth ( in wolverine), electra
also they have had some terrible castings: spider-man (entire cast of every film), lady deathstrike, daredevil, 2nd hulk character design
on a side note now that they have picked chris, i hope they have cap move like emil blonsky when he fought hulk in the park ( pre abomination) - to me that was classic cap america. ( he was supposed to be on the serum though so he should have moved like that)