It sucks insane power. Namely it drains every other system.
Not precisely true. It requires almost full power to run the cloak according to canon, but that doesn't mean the cloak drains any other systems. To be fair in canon full impulse doesn't drain anything either, that's a pure balance change.
As for decloaking and firing that's done in just about EVERY canon source out there, it's the definitive Klingon tactic. A lot of the time the image is still wavering (still decloaking) when they open fire in the canon sources.
Power drain is a pure balancing issue, and it would severely nerf cloak to do this, so I'm personally against it.
Also, as an aside, posting a thread and adding "I'm not going to come back and read this" is not a good way to demonstrate that you're a mature individual. It's a bit childish to be honest, like calling someone stupid then sticking your fingers in your ears and saying lalala.