I'm using a Kitkat 4.4.4 based phone (Samsung Galaxy S Duos 3) For the most part I don't use G+ or Maps or most of the Google apps provided. But I do prefer documents being backed up, so I've refrained from shutting down the google app entirely.
Being a phone of very low ram, it kinda cripples the performance. As far as I understand in Android it's not a good idea to kill apps (so normally I hibernate the stuff I don't use). I prefer having the RAM full with apps I actually use.
I'm not really sure what I should be doing with the Google apps. And I would prefer not voiding my warranty by creating a swap partition (using root)