I don't want the Cantrips to be consuming higher level spell slots normally is the only thing. Quicken will still apply only to the Cantrip, new class feature will explain why once I finish proofreading my update.Allow infinite domestic metamagic use and allow the use of quicken spell with it. Even then it's a little underpowered, but that way it is interesting to use. Is the spell list different from the Sorcerer's?
His spells of higher than Cantrips are going to be adaptations of the Cantrips, intended more often than not to represent his development as an adventurer. The truly Domestic ones will never gain higher than 1st level, after all.Fluff, fluff, and delicious fluff. No 9th level spell has domestic uses, aside from Wish. Meteor Swarm has absolutely no use in a non-adventuring environment, which is where the Domestic Sorcerer stays. Nor do I usually want to use Wail of the Banshee to do the dishes, or after a night out drinking with my chums.
Personally, I might be inclined to give them the ability to cast lower level spells at will, to demonstrate that their energy is going somewhere: maybe 1st level spells at will at 4th level, 2nd at 8th, 3rd at 12, 4th at 16th, and 5th at 20th?