To me it all depends on what type of guardian you are I use the hunters agility to res teammates and draw enemy fire and supers are mainly for mob clearing Warlocks can heal faster than the other classes and get back into a fight faster and deal more damage to bosses and the self res is always good for nightfalls and raids and nova bombs are like long range FoH Titans are the support class taking more damage and keeping that damage off of their more flimsy teammates and clearing mobs with FoH and protect teammates with their bubbles This is all for pve btw not for crucible