I suggest you try out the search function on the Forums.
I was once DKnight1000, apparently I had taken my own name so now I'm DKnight0001. If I ask you a question it is not an insult but a genuine attempt to understand why. When I insult you I won't be discreet about it, I will be precise and to the point stupid.
It may not look like much, but I can tank an elite cube and gate and deal 4k consistent DPS at the same time. Now, I know that 4k DPS is nothing compared to a pro escort hitting 7k, but keep in mind that I'm an engineer officer and tanking is my MO!
To answer your item questions, you want to get mark x weapons and start running normal STFs. 10 runs and you can get the borg engine and deflector. Before you run STFs, beat the mission 'assimilated' to get the assimilated borg console. 3 set borg will gives you quite a bit more survivability, and trade any rare salvage you get in for mark x borg weapons.
With the Galaxy's ensign engineering, it's got plenty of space to run emergency to shields AND weapons back to back inbetween eachother. If you hit EPTS, 15 seconds later in the middle of it's duration, EPTW will come out, and 15 seconds after that, your second EPTS, then your seconds EPTW, then back to first EPTS, they'll overlap nicely and it'll hopefully mitigate power drain. Also, it'll add a small damage bonus for the first 5 seconds. I think it's five anyhow.
Also, if you plan on using Eject Warp plasma, it's good to spec into particle generators. As you're using a Galaxy R as a tac, I'm assuming it's mostly for PVE and STF, and a well speced Eject Plasma III will do nasty things to any NPC. Burns through hull, and lowers defence value increasing the likelyhood of crits, which is especially handy with beam overload.
If you got two purple conn officer doffs that reduce the tactical team cooldown, you could run Tactical team, overload 1, and overload 2. That'd give you two spikes more than you have, and provide shield balancing as though you had two tactical teams on your power tray thanks to the doffs. Tactical team whilst mainly used for balancing shields and cleansing tactical debuffs, also provides a small damage boost.
Paired EPTW1 (above 1 doesn't help much), paired EPTS2 or 3 (3 is much more durable but costs you your LtCmdr slots that could be other highly useful stuff, so your call), and 6 beam arrays. The EPTW helps control the drain, the EPTS boosts your shield regeneration/damage-reduction, and 6 beams gives you an ugly broadside. You only have 1 tac team, but you can use tactical initiative to pretend you have 2 for 45 seconds at a time. For the Lt Tac slot, either FAW2 with all the beams, a torpedo2 skill, or mount a fore DBB or two and carry Overload 2 (and an EPS Flow Capacitor) combined with APA for a big spike.
Aye, but the reason I suggest 1 is because there's three ensign engineering slots, and if you don't put Emergency to X in those, you're putting Engineering Team in, and that clashes with tactical team which is generally much more useful and with Tac Initiative or the right conn officer doffs will work back to back from just one copy.