I like the idea of CiCs/SiCs having control and visibility so they can do the best job they can for the alliance - just like they can change rank they should be able to turn hidden on/off as needed.
We do require it is off at all times except in some war situations where we think there may be a spy in the ranks - we actually mandate it be turned on. I'm sure you've all seen those situations where people suddenly are being attacked right after they log off. ;)
I also like the idea of even when it is on CiCs/SiCs can see past it, not only to make sure players remain active but also when you need an attack group together during war - you will know when all the team is there and can skip the random "is xxx here?" in chat (which also can tip off spies as to when an attack is possibly coming)