Step 1 (Skills): Respec using the readings from here: http://home.comcast.net/~amicus/Skill%20...ffects.htm It's generally better to put only 6 points max in most of your skills except your focus since the results have strong diminishing returns above that, and your gear will add a lot of points to make up for that change anyhow. For a Tac, I suggest you do something like what I have here: http://skillplanner.stoacademy.com/?buil...ptors_3155 Feel free to play with the sci/eng abilities to suit your needs, but for a proper shield drain build you ABSOLUTELY must have points into Flow Capacitors. I suggest 6 at least but you could do 9 if you want. For Tac, make sure you max out the first 3 skills in the top and bottom tier, you probably want zero in threat and stealth because you like escorts, and then put as much as you can into your Energy and Projectile Specialization. If you want a look at a build that uses a lot of tetryons plus torps, I have another such build on my Avenger here: http://www.stoacademy.com/tools/skillpla...pboat_3155
Step 2 (Gear): Get fleet variants on your tac consoles for more damage. I suggest a mix of tetryon and photon vulnerability locators from the fleet Spire, either 2/2 or 3/1 as you have now. Photons have a fast refire so you could probably slot two photon torps fore if you wanted; that's the reason I have 3 on my Avenger build above since it has 5 fore weapon slots. You can do the same kind of build on an Andorian escort if you want although they aren't as survivable. Get fleet Neutroniums with +Turn or fleet RCS with +AllRes from the fleet Dilithium Mine. Dump the fleet engines for one of the Rep sets like Counter-Command or Assimilated Borg. If you want more shield drain, get the Omega Rep deflector and shields for the 2pc bonus of Tetryon Glider, this will drastically amplify your shield drain. For Sci consoles you should consider using 1-3 fleet Embassy consoles which add Flow Capacitors and possibly +Pla for the extra DOT from plasma burn; drop the emitter amplifier first for these, and if you want more then drop the field emitters also. You could consider changing your tetryon types if you want; check this post I made for more details: http://forum.stoacademy.com/showthread.php?tid=2112 There are some good freebie tetryon weapons from storyline missions that you can repeat. Also consider Dominion Polaron as it does both power drain AND tetryon shield drain, although it is polaron-energy based so you would need to change up your tac consoles accordingly.
Step 3 (Boff abilities): I'd leave most of this alone except drop Tractor Beam for Sci Team 1 if you remove your field emitter consoles. Your tac loadout is sufficient to do a lot of damage.