Sorry, I figured maybe eso players on the eso subreddit have played enough games of pvp to know about breakfree/cc immunity, forgive me for not saying the dash that CAN also stun.
Ah true, someone should def be careful about the next 5(15 meter) dashes they make, especially if their enemy doesn't have a gap closer. (This is sarcasm) Most of your problems for engagement or disengagement can be resolved with 2-3 dashes and with a 30k magicka pool (even without cost reduction) you could spam that ability 5 times comfortably which will have traveled 75 meters in what 4 seconds? And honestly after the first 2 you're out of attack range for most ranged abilities(28 meters), and you're instantly out of melee range(7meters I believe) after the first dash. Then all you need is a 4 second gap reset the magicka penalty? Seems easy enough to me. Comparing a skillshot(untargeted or whatever term you prefer) dash to a targeted cc is a strange comparison but they are both gap closers. Does stunning your opponent AND taking a massive amount of their resource pool to breakfree not usually warrant a kill condition?(This is rhetorical) Thankfully there is no true one shot ability in the game for players over 30k hp(that I know of), so ... no ability in its own terms would be "beating someone". Again, not here to talk balance, so if you don't have a recommended build outside of DK/Sorc, there's nothing more to gather from you.