Im all for having complex system.
Heck, I loved WHM in ff11.

You had so many spells aside from cures 1-3 and a handfull of heal over time effects.
You could raise resistance to every element, you could "precast" raise via the reraise spell.
They could raise resistance to things like paralyzed and poison.
You could even raise STR and INT of party members...
Was all of it useful? No.
But it was nice to have for times that did require it.