R4 Carnage or R3 Venom?

Wrathbert

I have a 5* Carnage and Venom (both unawakened). I have enough catalysts to R4 Carnage but I can also R3 Venom, who I think is a little better. I'm having trouble deciding which one to rank up first. What do you guys think?

Sarvanga1_

Rank up venom