I was wondering why you were going double red and dropping a yellow until I saw that you didn’t have one.
While I’m not of the opinion that either Frida or Evelyn are that strong on a defensive setup, I think it’s wiser to stick to rainbow as close as possible to make things more difficult for the attacker. I agree that the Zim-Magni-Kunchen-GM-Evelyn setup seems like the strongest layout, and as far as defense goes, it’s hard to beat a Kunchen tank, especially flanked by GM which makes it a pain in the butt to deal with. Because of Kunchen, it’s a bit hard to swallow the idea of adding another purple. Though a Seshat on the wing sounds like a pain as well, I think that’s just inviting a blue/yellow stack, whereas it’s not as obvious when you stick closer to full rainbow.
Maybe swap Zim and Evelyn’s positions, since Zim’s cleanse isn’t as critical with Kunchen in your center. While it means nobody gets Zim’s attack bonus, it does mean that Evelyn’s dispel is more likely to clean off any buffs before the rest of the defense fires, and a Evelyn-Magni-Kunchen left wing sounds more distasteful to fire into than a Zim-Magni-Kunchen defensive wing. But that puts two reds on the right, so maybe swap the flanks around. Evelyn-GM-Kunchen-Magni-Zim?
Idk. It seems like such a minor difference, but mirroring the defensive layout feels slightly more intimidating, if only by a bit.
I mean you’ll easily keep diamond with most any layout, so long as you keep up your attacks and punch at or higher than your weight, so I don’t think that’s as much of a concern. Hopefully you’ll get a great yellow like Joon or a defensive lineback like Justice or hopefully something amazing like Guin or Delilah, but who knows.
As far as purple, for defensive purposes its hard to top Kunchen unless you pull Boss Wolf, so of what you have, Sartana and Seshat are the front runners, and Seshat is about equal in damage output to Sartana (from what others have said) but is slightly more versatile with the minions and the dispel, so I think she’s the clear choice based on what you have.
My two gems.