Which Earth based Marvel 'Super Heroes' would get into the JLA ?
Probably not many :
Don't forget the JLA, is the best of the best. Think Grant Morisson and his Godlike patheon approach . (E.g. they are not a team of super heroes as such, but a set of Gods protecting the planet from 'Titanic' threats ). These guys are not going to be fighting Ninja's and will regularly have to contend with saving the entire universe. Note that the threats they are facing are usually on a level with the Avengers greatest 'powerhouses'. So anyone who is going to join must bring something that will significantly improve the team.
Recommendations :
Iron Man; Is regularly portrayed as the Avengers second most powerful member. In most ways he seems a lot superior to his D.C. counterpart John Henry Irons, AKA Steel. His character and genius would allow the team to brake away from their dependence on Batman, to provide them a scientific edge. I would also love to see his armour with some Kryptonian upgrades and re-united with the mother box. I also believe that he can currently physically compete with Aquaman, so added muscle will not be necessary.
Other suggestions :
Spiderman ; Wit humour and a much needed sense of morality
Iceman ; Although a significant improvement in character would be needed, he has vast potential !
Storm ; The league has no one with control over elemental powers, she is also and a strong leader. Her human vulnerability maybe a weakness.
Photon ; With the exception of Green lantern the league has no real 'spatial powers' Omniversal telepathy is always a good thing !
Doctor Strange : Although Fate should really be on the team, he isn't and Zattana should not be allowed back after her past mistakes. Strange is surely on par with Fate, and has gone up against some of Marvels most powerful opponents. I’m sure the Dark Lord Mordru wouldn't be too keen on up going against Strange.
Wolverine : Nah only kidding !