3 heals is a must. It's great, the regen boost is much better than in Fast Healing. It's not really expensive but I guess a stalker might still want to slot some endurance reduction since you don't have Quick Recovery. I'd start with 3 heals and see how it goes.
Yeah 3 slots for heals, it can be a bit end heavy, am lvl 37 atm and dont have stamina, but so far i've found it better to slot endred's on my attacks mainly, end gets pretty low after about 6-8 minions on relentless and has pretty much recovered by the time i hit the next mob, probably use rest maybe twice in a mish so not too bad, but my health bar says pretty much full unless i'm in a group of around 5 nasties or fighting bosses.
Takes around 14 mins to solo a warburg mish, and thats with claws.
I have no idea what to do. Is the heal any good on it?