Did primal spells push BLU into a corner?

[Seraphor]

Personally, I think they missed a trick with the level 70 spells.

I think what BLU is in need of is a way to use the Limit gauge. 'Limit Breaking Spells' could be a useful and unique tool. Powerful spells that consume the limit gauge, maybe even partially, so they could consume one bar at a time meaning a full party could allow three players to use a limit break spell.
And the reason why it should have been in the level 70 range is because you had some great primals and bosses that could have provided them. Suzaku could have given a healer LB with a party raise, Susano could give the melee single target LB or the 'ranged' line AoE LB, Shinryu the caster LB, and Omega the tank LB.
Crucially, this would have meant all of the primal spells at level 70 would occupy only one single slot instead of 2 or 3.

There's still potential for level 80, but I don't think it would be as fitting.
Hades would probably provide the 'caster' LB, Innocence the 'ranged' LB, tank LB from one of the Weapons, maybe healer LB from Titania.