I'm an oldtimer that is still getting used to Homecoming, and I pieced my build together from a handful of different posts so take this with a few grains of salt.
I was looking, and your end regen is better than mine. I went with dark for my epic, but almost never use Dark Consumption for end. I could easily swap to leviathan and just eat more blues.
I think the difference between our builds is that my Hasten has about 10sec downtime and that my heatloss has a 101sec recharge while yours is at 141sec. If the team can group 4+ mobs for you to hit with Heatloss, it seems to carry well.
I also have Performance Shifter: chance for +End in stamina instead of your chance to heal.
There is a real chance that I might not nuke enough leading to not feeling as much of an end issue. I'll attach my build on the chance it helps.
SF Water_Cold_Corr.mxd