Well as the Newtype is evident mostly within the people born in space, it's at least unlikely that she will have it. So as far as plot goes, maybe just interacting with Heero. Do Trowa and Quatra have the Newtype? Both are colony kids, so it's entirely possible that they do have it, and Quatra is a later generation.

I figure Heero's 'friends' are pretty much limited to the other Pilots, Relena and possibly a few preventers. He's trying though, bless his socialy retarded heart. You've ridden the line with Heero, he's gotten better, but you can't undo an entire childhood of training in just a few years.