If your GPP sucks, it'll be hard to include much volume. If your not getting enough volume, your body comp will go down the tube and you can't get as much training effect. Also if your GPP sucks, you'll have a harder time recovering from workouts.
I've seen a lot of threads about people having difficulty recovering from X amount of frequency or Y amount of volume and often better GPP would help people handle it and thus increase their rate of gains.
As a bare minimum just for general health, you should be walking 30-45 min. a day. It'll help your joints and recovery. Ideally, include some of the stuff you mentioned.
Right now, I'm having really good luck including some EDT type work for my accessories on DE days and reducing my rest periods in general for supplementary and accessory work. If I did the other stuff, would I be recovering faster... I think so, as long as I didn't try to add too much in too fast and eased into it.