You may be able to respec out of it after Power Sink is slotted, but I can't even begin to imagine the first 36 levels without Stam. I'm 37 on my BS/Elec stalker, and even with Stam I was huffing a lot before Power Sink just from attacks and running the 3 shield toggles. There are just times where you have to "scrap it out" when you're solo. I haven't decided if I'm going to try the staminless thing now that I'm high enough to have Power Sink up in 30 seconds or less, my build doesn't seem to "need" anything else right now. Elec/ or Dark/ may be different, it'll be up to you to decide.
I know my energy aura stalker replaced stamina with energy drain, don't see why elec armor couldn't do the same with powersink.
Energize is also a end discount power. With it and Power Sink, you can probably drop Stamina.
Running out of endurance can sneak up on you if you aren't using Power Sink a lot, even with stamina. That being said, yes, power sink really IS that good, and you could definitely get by without stamina, but you WILL have to use power sink far more frequently than you otherwise would, and if doing damage all the time is a major concern, it will somewhat deter from that, since you'd likely be using it every 30 seconds. With Energize up once a minute (more if you're going for a heavy recharge build) you COULD potentially have a 60% endurance discount half the time, though I personally save Energize from when I need the heal rather than using it for the endurance discount, speaking from my limited play on my Elec/Elec Brute since I16 launched.
If it helps, I have a brute with /ElA, and with some perma-hasten on the go, and energize on auto, I don't really notice a difference without stamina, but again, that's with a brute, I dunno if there would be a difference for a stalker.
I was thinking that, for once, I could break out of the Stamina habit with Electric Armor. I'd have a heal/+regen/end cost redux 3-in-1, and an end drain available. I was thinking either Elec/ or Dark/ as a primary.
Anyone have experience with this situation? Thanks!