Yeah she don't need a promotion but why stop at God Level when you can obtain Universe Level?
To be honest i would be happy enough if she gets Skill Act. after promotion. Just to boost the Damage output of the Counter Squad in Player phase a little bit.
I can recommend Tall Stewartia. She is a really good 5* unit. I had her in my old Debuff Team for a long time and due to her Life Steal she can survive a lot of attacks.
My battle waifu might become Rainbow Rose...5 more 10+1 rolls until the destruction begins