You stats are all over the place - killing stuff with assault rifle but only have 4 PER. The only good stat is 10 WIL but you have really low effective psi skills, no high level psi gears (headband, tact vest), can't craft high end drugs (focus stim, regenerative mixture, supersoldier drugs, trance, etc), no premeditation, no locus of control. You are already at level 27 so 3 level worth of skills point isn't going to change that. On top of that you are already at DC which mean you can't really go back to your house in order to use work bench to re-craft all your gears.
A better player than I might disagree, but I think your char is in a no-win situation against the final boss and the best choice here is to restart.