[MegaBlues]

Tomes could have parts which increase the power (in general or for certain domains), decrease FP consumption, adjust targeting range/shape, negate a portion of elemental resistance, etc.

There are people out there who simply stack power on weapons for autohit strength. Tomes shouldn't be left out simply because there are no hitcheck spells.

Also for possible tome parts, we have could have ink, binding, and font, for example. It makes about as much sense as changing the blade, hilt, and guard of a sword and still having it be the same weapon.