Aux is used to strengthen the cloaks stealth. The drain/recharge would be dependent on skill points and level. If you have FBP 3 and full specced into it you would have lets say initial drain drain of -5 for 3 seconds when it starts to recharge but if you have FBP 2 it would have drain of -5 for 5 seconds then recharge and so on and so forth. All it would do is make people be judicious with use of multiple aux skills. If you want to use 5 skills that are aux heavy you can expect a -25 drain with various rates of recharge to correspond to the various skill levels and points specc'd the numbers I am using are purely SWAGs for discussion purposes but I hope illustrates the mechanic I think would work overall and help PvP become less of a resist spamming it has become lately.
How does a cloaking thread turn into a full fledged nerf-science-some-more thread? No, just no.
On topic, the only thing that I think needs to be done with cloak is to remove the decloaking damage buff. It is completely and utterly unnecessary. The surprise factor is more than enough to do some serious damage before the enemy can react.
However, I've said it plenty of times, cloak detection needs to be very much refined into a much more in depth minigame of sorts. As it is, cloak detection is just too binary. You either find them, or you have no clue whatsoever. There needs to be a gray area in there, where cloak detection knows they are in the area, but can't pinpoint them.