I think that Shamash was said to be good at tanking single target attacks, but that particular role in itself can be hit or miss.

Atum's... interesting.
A 9/8 turn cooldown skill that reduces one ally's cooldowns by 1 turn. One of those skills that scream high potential but requires knowing what you're doing.
Very powerful single target heal (2000 HP + a barrier to eat 2000 HP in itself) on 4/3 turn cooldown.
And a 20 turn cooldown skill that.... ok, if you remember Life 3/Reraise from Final Fantasy, think that. Give one ally a buff. When that ally gets knocked out, automatically revive with 2500 HP.
Her passive's a 250 HP regen for herself.

Freyr's a hard hitter; she's got one of those maximal damage buffs. But instead of being against stunned, Frey's is against raging. 15 turn cooldown can be rough if 1 burst isn't enough. But she sure can smack the bejeezus out of a raging foe.

SSR Artemis has a A-frame -20% def debuff. Light hasn't had one of such yet.