OK, you did ask for honesty...
Theodora - no - sounds too precious, plus Robbie Williams called his daughter this, and I loathe the man! Like Dorothea though.
Persephone - really like it, and the nn Sephy, but suspect it might be a bit 'much', unless she'll be moving in particularly artsy or literary circles. Pronunciation/spelling issues abound.
Cliona - clitoris again, I'm afraid. Shame, as it's very pretty in theory. Love Clio.
Hero - I get the appeal (big fan of mythological names here), and I like the non-girly -o ending, but I'd worry she'd be facing a lifetime of justifying her name to others. ('No, it's NOT a boys' name, it's from the Greek myth...')
Eila - OK - not awful, but seems a little flimsy, and open to confusion with other similar names.
Darcey - not keen. I'm a teacher, and have come across too many stroppy and entitled Darcey/Darcie/D'Arcys in my time. Plus it rhymes with arsey.
Clara - quite like it, but its popularity has exploded recently - think it might date (the new Amelia/Sophia?)
Stella - I want to like it, but it comes across as a bit brassy and brash to me (perhaps because of the lager and Stella McCartney connections?). Much prefer Estella or Celeste (or Aster, which also means star)
Max - meh. Loads of them about.
Aengus - love Angus, but this spelling just looks odd imo.
Theodore - like it, and nn Theo.
Ethan - a bit plain, but I quite like it.
Luca - much prefer Luke. Luca is pretentious in a minor celeb sort of way.
Jeremiah - no - it's either American President or American Bible Belt loon to me.
Joseph - massively overdone imo, but it's a safe enough choice
Overall you have a couple of nice options in there, but none that personally stands out for me. Names are incredibly subjective, though, so in the end you need to take everyone's opinions with a pinch of salt!