>>1802157
You're probably not asking the right guy; I only ever choose things based on two merits:
>Does it sound fun
>If yes, are Harpies involved
I did get Ateru's EX II Skill in the previous event when it came around despite the fact that I don't actually own her at all, but that's solely because I was told that they had given out a guaranteed "pick your chosen L tier girl from this list" coupon at some anniversary in the past and she's the very first girl by order (to my surprise Charis was actually #5 by id) so hypothetically if they give something like that out again I'll be able to obtain her. I'm not sure if it was the best idea in hindsight, however, and I don't think I'd recommend it. Better to use what you've got to boost who you have, and only after you've done that should you probably consider it.
Still though I don't care how powerful or optimal a girl is if I do not like them I will refuse to use them until something alleviates my dislike of them. I only ever use girls I actually care about, meta be damned. So I wouldn't buy a skill for a girl I don't own if I don't like her anyways.
......well, 90% of all the girls I use here are still Harpies anyways, even after trying to branch out a bit.
The heart wants what it wants....