What I have discerned from itemization requests in this board
Mages need a new CDR item and tanks need a better tank item that is cost effective to deal with the surplus of true/max health damage
The Mage request can easily be remedied by bringing back the Lost Chapter items from Black Market Brawlers into Summoner's Rift.
As for that Tank item which would counter true/health damage, it's a complicated predicament due to the fact that Juggernauts and even light fighters/duelists can also abuse tank items to become obscenely resilient while doing high damage. It's likely it would end up gimped just like Thornmail Armour. On the other hand, this item could be a godsend to deal with the insane amount of true/health damage champions who are dominating. In either case, it's a bitter pill to swallow.