I like Teia as opposed to
Tea or Taya. It seems easier to say than
Tea (because you know there will be those people who simply say "tee") and Taya looks like the more common
Maya, and whatever else rhymes with it.
I like Teia/Tea/Taya as a nickname, but not a first name. It seems hard to find combos that have a good flow. (For me, anyway. I'm sure you could do it!)