So while i was modding i found an interesting bug you are gonna want to watch out for.

I was playing with warlock, and astarion.
I basically tried to make a warlock astarion. and what happened was the INT based cantrip that half elves get for some reason glitched out several spells and counted my int modifier as the modifier for a bunch of the warlock spells that are also on the wizard spell list.

I don't know exactly what caused it if its specific to Astarion, to elf cantrips, or if its spells that share with wizard.

Also if you plan to multiclass you may want to instead of granting spell slots from the class, you should instead create a profile for "Caster level" and have the classes grant "Caster levels".
I also recomend turning warlock into a full caster that focuses the lower level spells more, i have a ruleset that works incredibly well. im putting it into a mod.