I'm definitely not one of the best DPS Sages in game, I've only dpsed for like 1 month or so, mostly because I usually healed. I've worked on my DPS gear and I have 36% Crit chance, 76% Crit mult, 9% Activation around 1050~ Bonus Damage and I managed to do this:
TK Build Parse: http://www.torparse.com/a/99560/18/0/Overview
TK Build: http://www.torhead.com/skill-calc#60...0dorutzZcM0M.2
There's a TK guide in the forums wich is a nice help, but I consider that this spec requires a lot of attention to your buffs and the targets dots (Also I consider that TK can do more dmg to bosses if you have the armor debuff because you have more kinectic based skills than balance sages)
Balance Build Parse: http://www.torparse.com/a/99560/19/0/Overview
Balance Build: http://www.torhead.com/skill-calc#600hZbcMZcMfRsMkrfz.2
As some people said in the thread, just place your DoT's in time (when they actually wear off), try to avoid Force in Balance CD near Mind Crush CD so that way your Force Supression debuff is mostly used by Weaken Mind and Sever Force instead of Mind Crush (wich doesn't do a lot of dmg per tick as the mentioned above). Also for Balance you need more crit than TK.
I use 1 DG power relic and 1 EWH power one (working on another DG relic). For Balance you should use 1 DG power relic and 1 DG proc relic (I cant remember wich one is for sages but there are plenty of treads where you can find it) for TK I'm not sure if the DG Proc relic is good (mostly because you have cast times and only 1-2 dots on the target)
About the 1.9k DPS on the Operation Target Dummy I believe that's doable, as I said I don't think I'm a great sage dps and I'm not min/max for dps and look what I manage to do.
I hope this help you