I still think enlightened spirit could do with a little bit more love than 2 tier 5 enhancements being cheaper. Doesn't really address the issues
Just "a little"!?
ES T5 is completely worthless; it has no 25% HP node and no critical multiplier node (for the melee'ish tanks) and no useful DPS for the spell tanks -- an extra
unscaled 4d6 is pathetic. Even Shining Through is too small to bother buying (maybe 700 HP every 30s?). I get more from Guard-Up in the US tree every 12s and phenomenally more from rage/scream+blood feast with no CD (actually about 3s due to UI GCD).
Capstone for 20% HP is not the right place, too. The tree as a whole is so bad that 41 points in it is 10~20 wasted AP, which leaves not enough for fixing things via other trees.
Displacement used to be a big draw, but due to reaper nerfs it's become just "oh, nice" and then only if you don't have to work for it but get it as a passive on the way to nicer things.
I'd update it with scaling for the aura on 2xmelee OR spell power, give T5 crit+HP, scale the buttons (on both melee or spell), and add some new aura features (like tentacles). Having tentacles randomly spring up on stuff you're tanking would be fun.
Warlock is also ripe for a 5e'ish hexblade pass. ES could be polished up with ideas from that.