We should have a "Lance mage", "Ninja Sword mage", "Fist mage"

[Aiselia]

- Mobility is reduced, but the job's still the most mobile one in the game, by far.

I'd argue this.

Summoners have two cast-time abilities outside of DWT that are necessary to maintain. Ruin 1 does the same damage as Ruin 2 but you can move while using Ruin 2 and you have enough MP to use it during high movement phases. The only time Summoners are particularly locked down are for the 5 sec it takes to cast Bio 2/Miasma, then the <15 sec of DWT using Ruin 3 (less than because your last hit will be the instant cast DF).

Summoners do not suffer a DPS loss by using Ruin 2 over Ruin 1 if they need to move, while Bards would suffer a DPS loss if they had to turn off WM.

Oddly enough, I feel less limited in mobility while on an actual caster than I do as a Bard.

you can't have everything.

You also can limit mobility (if necessary) without adding cast times.

it's gained complexity

If anything, it has become less complex and challenging because the cast times give it a slower pace.