I got a little dilemma: Who should I ascend first; Vivica or Malosi? My yellow team is probably the weakest. Got Joon w/costume, Mist and Guardian Jackal maxed. Vivica/Justice and Malosi at 3/70.
Got 11 darts, so I’m ready to ascend one.
Malosi seems cool and handy on offence. Vivica is more of a defence girl imo. Ain’t got her costume yet either. My defence team is getting decent with Red Hood/Vela/Heimdall/Seshat/Joon, so neither of them will take a spot there.
So… who would you go for?
Imo i would go Malosi. Fast mana is no joke!! I own Vivica without costume or any emblems and i only use her for my mono yellow attack team(titans) and for war as well. Her slow mana bothers me more than any other slow mana hero i own.
I’d not call Vivica a defense hero. She is a cleanser, which is quite important in offense. Her slow mana is a disadvantage of course, but tolerable in most cases. So, if you need a 5* healer Vivica is a good option. Of course, if you don’t have Ariel already.
I know nothing about Malosi, unfortunately. He eluded me. 
I do use Rigard w/costume (+19) mostly as my cleanser, and i do think he’s a better option. Wouldn’t give Vivica his emblems either.
Well, this means you’ve answered your own question, haven’t you?
Personally, I agree with a statement that you can’t have too many good healers. On the other hand, I don’t have Malosi. 
I like Vivica, she already gave me great result in my yellow stack since 3.70 so long… so I ascend her, too make more little sturdier.
IMO it depend on playstyle and which is more fun to play.
Now, there is Lady Woolerton, fast healer yellow! 
but she doesn’t cleanse though.