I think honestly if they wanted the power system to make sense and be more canon they would have;
I seem to remember in the shows they always where charging the deflector ect.
Sci skill should have the same drain mechanic weapons do and run off Deflector power....
All Emergency power too skills should be... Aux power to... and the pool should recharge slower then all other systems... like a -100 EPS value or something. (Think like a big Hi Tech Capacitor system that charges off the warp core bleed or whatever... if it was instant power why would it be reserve or aux power right)
Won't ever happen... but its how it should have been designed from the start.
Why can't I use all of this so-called "emergency power" in non-emergencies? And why is there so much power reserved for emergencies? Oh wait... Cruisers can lolcycle 4 EPtX for constant +72 power. :p
Actually, you only need to lolcycle 3 EPtX if your doin' it right. Tradeoff is 2/3's uptime on three systems vs. 100% uptime on two, but freeing up an engineering slot makes it worth it. I use EPtA, EPtW, and EPtS on Jorfaid.