I would use regens more often if they functioned more like regen in FFVII, where it wasn't in intervals, but a continuous increase in your hp over the duration of the spell...I doubt they could implement that style of regen exactly, but they could make the healing intervals cut in half...I'd suggest a JA that does something like halves the duration of regens for twice the power or something, but I'd prefer just a change to the spells as imo they are meant to be like afterthought cures that we don't really have to focus on.

I'd also like to see regen's casting time and spell cost reduced (possibly scaling casting time and/or mp cost with healing magic skill?) so they are more mp efficient and thus more worth using than just cure bombing everything.