prevent them [Origins]from respeccing certain things about them, mostly class, subclass, deity, or other stuff that is relevant to the character
Agree - this defines them.
IMO first Class, Background, Attributes of the Origins should be set in stone.
If that was the case, then Durge or the Dark Urge would be stuck as a White Dragonborn Storm Sorcerer (literally their Canon Class and Race combo),
Auto level-up:literally seems like common sense. and don't give me any crap about "muh limiting player choice". if you want to play as an altruistic flamboyant bard, you can literally just do that instead of picking laezel? if you want to bring a warlock with you, take wyll instead of making halsin one. you can always mod this anyway.
I'd rather you don't mess up my Playstation game, a Better idea is how about make a mod that prevents multiclassing, prevents respeccing and auto levels companions, if you want what you're asking for you can just mod it in, there's literally no point in limiting the choices of BG3 players, who can't mod their games, if Larian did what you just asked, all of BG3's console players would be demanding refunds.