I wouldn't be opposed if these re-releases got added content. Metroid Prime 1 and 2 were already pretty stellar (more so 1 than 2... two was lacking something one had), so adding to them while not damaging what's already there would be quite nice. Also, perhaps they could fix that dead-end glitch in Metroid Prime 2? You know... the one with that one sound puzzle that if you leave the room while doing it (maybe you're low on health) or you have to suddenly go somewhere and save, the puzzle resets but the locks do not? Yeah, if you haven't saved in a while, it's a nice reminder to why you should save often. In a catch 22, if you saved after leaving the puzzle, it's a dead end and you need to restart your file ALL the way from the beginning.
...Yeah, they probably should look into fixing that.