I'd rather pick upgrades/changes to the organisation that have effects, as in BG2 than, curtains and fitting cosmetics like.. basically every other game.
But if BG3 ends up with our squads being pretty mobile, the camp slowly developing and changing backgrounds based where we are would be best, do we even know if backtracking will be an option? Maybe we will only be in BG for an act then off to waterdeep or something?