Tank Concepts
<<<<< Disclaimer >>>>> What Im about to Say would require an update the size of 2 seasons worth updates so its purely conceptual
I have been playing around in my head with the concept of tanks being tanky on a cooldown. For an example of this look at alistar. He gets massive DR on a cooldown.
To do this tank items would be retooled. No longer giving base defensive stats but giving things like %DR and the such. Also items that increase regen gained from all sources.
The 1 character Ive really put a bunch of thought into is Mundo.
Q - Lower damage. Heals mundo for 2/3/4/5/6% of his HP over 3 seconds every time he lands a cleaver on a champion (as well has fully refunding the health cost)
W - No Change
E - Buff the damage to compensate for the loss of damage on Q.
R - Removes Grievous Wounds and makes Mundo immune to them. Same healing over time. No longer costs anything but actually gives him 200/300/400 HP instantly on activation.
This would mean that when Mundo's ult is down he is more susceptible to burst but when its up he cant really be stopped unless you load all your damage into him instantly before he can pop ult.