OP here personally I dump Intelligence, since only 2 classes uses it as their main stat and one of those 2 classes aren't even in BG3.
Not sure what you mean, the wizard class is in BG3 and it does use intelligence as primary stat. But I think the stat that isn't a primary for any class is constitution...it will often be a secondary stat for strength based classes but if you play as a caster or ranged character you don't need constitution. Over the course of the game 12 hp more or less won't make a huge difference. I probably won't put it all the way down to 8 but usually leave it at 10. It's one of those stats that is just kind of there as I almost never play tank characters.