So I know some homosexual people myself and have no trouble with that, but yeah...the imagination of MJ suddenly outening as an Brazilian transsexual, is for me as someone that is highly visual thinking...yeah...^^. Additional for female readers of spiderman, its sad...I mean spidey always had that, very, very close costumes, where not much room was left for imagination. ^^ Other superheroes have that as well, but he always had that "not being always so earnest" touch, that made him sexy. I mean Thor is always telling pathetic asgard stuff, Captain America is so holy you can puke, Superman mostly is presented as someone so prude that the look of a womans breasts were more deadly for him then cryptonite, Cyclops is simpy a lamer that shares his sex appeal with pope franciscus...
Dont know, Spiderman and Wolverine have always been the cool boys, not the "We have to stay earnest, everything depends on us all the time."-grandfathers ^^, so him getting homosexual would be a bit sad.
I have heard that they wanted to reset the whole comic series the next years, with new painters and so on, so I think it would be better if they would present a new guy or gal in one of the bigger groups like the X-men, or add an "from now and then" sidekick to one of the soloheroes, that they could give an own series, when he/she becomes popular.
Edit: Didnt come up right to my mind, but bi-sexual and adding an additional partner to MJ would be absolutely ok for me. 