Please make it possible to switch loadouts in the middle of a flashpoint or Op (any group finder activity). It is very frustrating if your group cannot progress because (for example) the healer disconnected and no one is able to join. Knowing that you can do it yourself, but the game does not allow you to swap loadouts.
Another such example: While in tank spec, I signed up as DPS or tank (I can do either). The GF gave me a DPS role, but subsequently did not allow me to go into DPS spec (so had to complete the content as a second tank
I understand you don't want people to abuse the system and swap all the time, but a simple timer can fix that (don't allow players to swap again for 5 minutes or so (while still in the same GF activity)