I am running a Elec/Psi Dominator as well, making my way to perma domination. I love not having the need for stamina on this char, and Psi is coming into is own now that i have some aoe at level 40 so far. I have noticed that fighting Rikki and Malta is a pain with with this char so far, but other than that, great fun.
Should have started this a lot sooner, but I finally got my Elec/Psi Dom up to 22 and got her first full suite of SO's, which is really the beginning of the majority part of the game. So I thought starting now would make just as much sense as anything.
So Psilapse: Recently escaped Praetorian, now a Blueside Hero.
I went with /Psi as a pairing with Elec/ as I figured the -Rec from Drain Psyche would make a big difference when it came to the effectiveness of sapping. Psi also has some of the best AOE dmg, and the durability provided by Drain Psyche is unmatched, which also seems to have excellent synergy with Elec's focus on sapping.
How's it working so far? Pretty well. I still need quite a bit of slotting to get a real feel for it, but the difference DP makes on sapped mobs is quite dramatic. Without DP, mobs get bits of end back and can still get off attacks periodically, with the -Rec from DP in effect they are totally helpless.
Will post more later with my (somewhat screwy as I've been playing with things on the way up) build, and some more specific observations.