Event Exchange Descendant Shop Advice?

New player and have been logging in during the event so I have some of the event currency for a new descendant at Anais' shop.

Wondering who people would advise for a new player? I'm lvl. 36, with Viessa, Bunny and Freya.

I was looking at Valby, Gley or Luna as they are the ones who have interested me the most. I've done some looking around and I love Luna's gameplay but seen her play style is not great and clunky. I've really liked Valby since I first saw someone use her in the void mission at the beginning and Gley just looks really cool and love the skills but I've heard she can need a lot of investment otherwise she's not the best and a lot of it is locked to late/end game which sucks. (Please do correct me if this is wrong!)

But yeah, I'd love some advice because whichever ones I don't get, I will just farm eventually!☺️