IMHO Clarissa >> Malosi. Even after nerf, she is still poisonous GM, so I would chase her. That being said, new costumes are coming and will be likely out in May (as new patches are rolled out on monthly basis, usually towards the end of the month) which has double effect:
- Positive: You have shot at getting something new for 3* and 4*
- Negative: Dilutes pool of 5* you want, unless they are featured (but then again Magni, Sartana are still desired).
I would wait. Of course option number three is to pull in Valhalla (what I will do if Alfrike will be featured) or Atlantis (GM should be there, but so will be Atomos…). But from pure HoTM view, waiting for Clarissa is better.