I think there should be a new tenacity item

I'm not sure exactly what other stats it should give, but in terms of tenacity I have a cool idea. It's passive should initially give no tenacity, and have this effect:

When you are afflicted by crowd control, gain 50% tenacity for 2 seconds. This effect can stack with itself. Remember that tenacity stacks multiplicatively. So in other words, if you get hit by a 1 second stun, it lasts for the full second but you now have 50% tenacity. The next 1 second stun that hits you (within 2 seconds) will last only 0.5 seconds, and a third will last 0.25 seconds, etc. I think this item would be a cool counter to annoying chain cc.