I'm currently running this
. I would have preferred getting the immunity and sturdiness enhancements instead, but I couldn't find a crafter nor find them at any of the black hole/campaign vendors, so I had to make do with what I could find.
It's not perfect, a WH defense relic combined with swapping a bunch of defense augments for absorb would probably give better overall stats, but since I don't like PVP that's just not something I've gotten around to acquiring yet.
Current progress: EC HM 4/4, TFB HM 5/5. Haven't had a chance at EC NiM since it was our other tanks turn in the rotation when we did that.
I've actually changed my mind on defense since then - I made that build by swapping mods around on askmrrobot and doing some math in my head to try to figure out the best distribution, but I made the mistake of calculating defending an attack as mitigating the full damage of the attack, but a large portion of the undefended damage would be shielded and/or absorbed by armor anyway and is thus worth a lot less then one might think at first. Since then, I've made a spreadsheet to calculate the actual total mitigation, and it shows that max mean mitigation is achieved with defense somewhere between 350-400 (including the bonus from your fortitude stim) depending on your total amount of mitigation points available - if you're using 27b mods it will be about 350, but if you use 27 unlettered mods it's about 400, both numbers are assuming that you're using a proc absorb relic (which was also shown to be vastly superior to a second static defense/shield relic, mean damage taken went down about 10% assuming it takes 4 seconds to get the proc back up after each ICD - however that's assuming that you want to keep your HP at the same level as it would be with the static mitigation relic, which would mean swapping 3 mitigation augments for endurance augments, thus reducing the static gain you would have recieved).
Considering all that, my new goal build is this: http://swtor.askmrrobot.com/characte...4-d8861785338c
I've switched to 27b mods mainly for Kephess in EC NiM - he puts out a lot of unmitigateable damage in short bursts, so I want to have more of a buffer for that, but the endurance augments honestly aren't really necessary - that's mostly a "I'm so close to 29k anyway, I might as well just push it over the edge".
Absorb may seem a little low, but there's an extra 455 points in it about a quarter of the time so raising it higher causes serious diminishing returns when the proc is active, which compensates for the slightly lower mitigation while waiting for the ICD to run out again.
Tl;Dr, that's the absolute maximum mean mitigation you can get out of your gear assuming that you want that amount of HP and that it takes 4 seconds to reactivate the proc after each ICD.