The fix for tanks

I feel that the main issue with tanks is their upfront damage that they can dish out to the whole enemy team. They feel almost like bruises that can get away with building full tanK while doing tons of damage and large AoE. I think riot went in the right direction with Cinderhulk (scaling damage over time), as this reduces a tank's upfront damage, but still makes them relavent in the fight over time. By shifting tanks in this general direction, you would also be rewarding building tanky, in order to last long enough in the fight to do constant sustained damage. It should be more akin to a tankier but also less damaging adc rather than a tanky bursty bruiser. Their strengths should lie in their strong defence and cleanup after a fight, along with some elements of engaging and lockdown,rather than some running in and doing tons of damage.

Tl;Dr Make tanks deal less upfront damage and spread the damage over time, so it scales up the longer a fight goes.