Use Teddiursa because it is a bear and bears are good.
Store Lunatone because I have something of a soft spot for it.
Release Lunala for spoiler reasons. It doesn't belong to me.
Edit: Almost forgot to offer three.
:alolanpersian::purugly::liepard: Purple(ish) cats.
@chidzz How does Yanmega sound?
@Kaori Since you seem pretty set on your starter I won't choose that, and will instead offer up your choice of Solrock or Lunatone. (Mostly because I'm not sure if they're version exclusives or not.)
8/10 A good, strong starting game bird that manages to hold up in the late game thanks to its strong statline and - for its time and archetype - fantastic movepool. Definitely used one a few times in Gen 4. It's no slouch in the looks department either.
So let's bring it back to the original...