i think it would be cool if you could fire when cloaked, however doing so will partially decloak you. when you cease firing the cloaking device gradually recloaks you over a couple seconds. same should go for afterburners. i still think the variable cloak thing has potential for some awesome gameplay.
a new ets is a must though, the more gauges you have, the less power to go around. power is a concern to any ship with a cloaking device. when cloaked your shield, weapon, and afterburner energyshould slowly drain. thus the longer you stay cloaked, the more vulnerable your ship will be when you decloak.