i pulled and 6 starred a fire mermaid as well
she is my only reviver and i rly love her
IMO the revive of briand seems better since he balance the HP of all the group but it could be annoying too if your team is low hp and if you haven't your healer just back
The advantage of mermaid is her skillset, buff removal on first skill, revive or heal + atb boost with 2nd, stun + silence with 3rd
Depends on if you prefer fire over wind lol