Game mode suggestion: Nostalgia
A game mode that is like a common normal game on Summoner's Rift... except for the fact that the old items are back.
Old items like Force of Nature, Deathfire Grasp, and even old jungle items like Spirit of the Elder Lizard. Imagine mages with Deathfire Grasp and Zhonya's Ring!
Of course some of those items would have to be tweaked to fit with the nowadays stats. For example, Force of Nature would have to give 200% base health regeneration instead of the 40 flat health regeneration that it used to give.
I am suggesting that because I've never had the opportunity to play back when FoN used to exist, and I somewhat miss Deathfire Grasp (though I agree that it was a toxic item). What do you think?