VKF's Rapid Slash doesn't stack with Killer (which you pointed out when I made that build ); non-VKF makes more sense if you're going that way. Fighter stance is really strong IMO, 25 PRR/MRR & 20% HP in Heroics (+6 Con epics) is a big difference in survivability, especially if you're newer without PL's etc to add on.
Johnny posted on Reddit as well, and I definitely also recommended RMM+BE Artificer there lol.
I wonder about dipping /1 into Alchemist (and maybe Warlock if it's a TR toon) for Soothing Poultices (plus Feigned Health if Warlock). Massively improves the efficiency of your cheap heals, at a fairly low opportunity cost assuming this is a 1-20 run. 2-4 SP SLA for Curative Admixture for super cheap group application as well.