The change in the weapon power drain mechanic divorces power drain from power transfer/recovery but not totally. Weapon Power drain now drains X power from weapon power during the firing cycle, and restores X weapon power back instantly. There are very small slices of time in which power recover happens between drain/restore cycles. I've tested out various combinations of #'s of weapon firing and 1000%+ Power Transfer Rate. So enhanced Power Transfer Rate (i.e. RCS Flow consoles, Starship Electro-Plasma Systems, etc) does help a teeny, tiny bit. The effect is miniscule even at massive amounts of Power Transfer Rate. As coarse of the game UI is I figure the effect is around a net of 5 weapon power.
My advice is to only use get enhanced Power Transfer Rate (i.e. RCS controls, Electto-Plasma Systems Captain Skill ranks) to recover faster from a Beam Overload or the Dreanaught Phaser Lance ((weapon power drain mechnics won't restore that). Or if you change power settings in the middle of combat (or just before by using Full Impulse). RCS consoles for purely Energy Weapons is a wasted slot. Put something else in that slot like an Armor Console.
I run a fleet escort disruptor beam boat and I'm always in the top 3 in fleet actions (most often 2nd though). I even out-dps some of those cannon+turret defiants, but I'll admit it's most likely only because they're not good pilots and don't know how to use what they've got. The #1 spot in fleet actions that I'm in usually goes to one of the good defiant pilots, although I changed up some boff powers recently and now I get 1st more often. And I should note that's without respeccing from my current terrible skillpoint investment.. I expect to see further improvements after a respec that caters to my needs.
I should note that I don't pvp, period, and that I would probably get curbstomped if I tried with my build. I've also never tried an elite STF with this build, but it works well in normal STFs.