I'm sort of surprised your asking these questions and playing 100nl 6max.
This is very general sort of topic, but really it's a lot down to villains stats/reads, what type of pairs etc. BTW calling for set value in 6max is not generally that good of an idea, as there is generally a lot of value in pairs alone, without the need to play them passively for set value alone.
As you probably know, 6max is all about aggression, and the further up the stakes you go even more so. So generally speaking, PP's have plenty of value, how you play them oop, is very much villain dependent imo.