I think the other thing that should be considered is whether or not it's adventageous to have lots of ailments with low amounts of stacks as opposed to a lower number with a lot of stacks? You can turn a lot of abilities into Aether, and thus could hit 30 stacks of those 2 plus to the two poison ones pretty easily. I realize that blades have a skill that increases damage per stack, but by how much? Is it better than having a bunch of stacks of weakness?
I don't turn plagueburst into fire, I use the Plaguebringer skill instead to boost it's toxic damage capacity (getting lots of green globes is not a challenge). I just miss out on fire damage, boo hoo. I get toxic, aether, shadow, sacred, and frost right now with my build - when I unlock my 5th slot I'll probably add another. The rend gem idea is interesting though, i like that.
I use spherical repulsion to regen shields, and have zero issues with it. Won't have the points for Salvatory Anchor.
As far as stats go, I've been doing a 6/2/2 breakdown of ferocity/tough/wisdom. I get ailment applications easily and my crit rate is over 50% just from ferocity right now (I'm lvl 53), which of course causes more ailment applications with Primordial Insights.
This is the build I'm headed towards right now:
https://tinyurl.com/us2gs7v