I'm doing mild save scumming, not to have a flawless playthrough but because like you say it's a huge game and I don't have a million spare hours so odds are I'm only going to do one good serious playthrough then take a break and maybe do a evil play through or something later.

It's not like I'm going to see everything so I might as well use the magic of time manipulation to explore alternate realities - the characters talk about that sort of weirdness all the time so for me I don't even feel it's world breaking.

Though honestly the only mistake I wish I could go back and fix is completing pretty much the whole first area with only two characters because I missed talking to all the NPCs who'd join me - did make it more challenging tho which was fun I guess.