Wouldn't want to write the X-Men, and I suppose the X-Men is the ultimate Marvel comic, and I really wouldn't want to go anywhere near it at all, although on the other had I wouldn't mind having a crack at something like the Punisher.
It's nice to be in a situation where the two books that I write for a sort of regular monthly income are also works that I enjoy immensely, rather than them being some kind of bread and butter, do it because you have to do it.
If you look at Marvel Comics, there are very few Marvel characters I would like to write.
I don't necessarily write everything as automatically assuming it will be collected, there's nothing that says Hitman will be collected, though it might be.
I tend to forget what I'm doing will ever be read while I'm writing it, and just get on with the task at hand.