Need help

ZAHIDMALIK1588

I really can't decide who to R2 at the moment. I have enough resources for cosmic or mystic plus I have a rank up gem 1-2. Thanks in anticipation. Here is my roster for better clarity.
PS: Nimrod is going to R5.

Strangecraft069

Knull, sigil witch, kingpin, 5* ghost (better at Max sigs)