For me, double healers, not so much. I've played Azure for far too much and too long to know how to deal with.

Triple could be problem when the enemy team has Kage Tsunade.

Kabuto is meh now, since he got nerfed. Shizune is in the same row as Kabuto. But if she was Water, PHWOAA! She will be hella stronger than this.

Arena base

Max heal from Azure with 40% healing tip in arena gives 1200 hp. (Not including Tsunade healing tip 45%)

Sailor 900

If triple with Tsunade, she gives 45%. Therefore only Azure heals almost up to 1800 hp per round.

As f2p the only team so far i beat triple healers in arena (ONLY) I've played with was.

x-x-x

AF - x - Roshi

Yugito - Sailor

Trumpet, Chamelon.

Yugito will hit last this will trigger Roshi ignite chase.

Replace Yugito with Yagura for better CC and combo.