What do you think about adding some kind of health return for every player, who is under the effect of crowd control? Like when you get CCed you gain 2 or 3% (it could be more or less) health every second for the duration of cc. Doesn't break on damage, with exception of Mage's Polymorph and other such CCs.
So lets say Warlock fears you for 6 second and then Rogue Cheapshot you for the next 4 seconds. You will get 2 or 3% (it could be more or less) health every second for the next 10 seconds. Same for almost any other kind of cc.
That will force players to CC the ones they want them to be "removed" from the battle for a short period of time, while damaging another enemy player and not be able to kill them in stunlock or Fear any more. So you will have to use your cc wisely. The one who gets CCed will be extremely hard to kill 1v1 or 2v1 for the duration of CC.
Sry for eng ...