I think
Maia is pretty. Spelt this way I pronounce it "MY-uh", spelt like
Maya, I pronounce it "MAY-uh". I prefer
Maya.
I don't know if it ages well, I have never met an adult
Maia. However, it's not too cutesy and there are plenty of 4-letter names ending in A which age really well, so I don't see why not.