Zeraph

I think energy users are at a small disadvantage because there's less itemization for them, and they run out with 1 combo, meaning they can't spam in team fights when it really matters.

Garen and kat are probably also balanced, but I have less of an opinion on them. Garen has no range and kat is squishy without a tanky build.

My main issue is that things like wit's end (not too big a deal) and Veigar (big deal) are much less useful against them. But that's more of a design flaw than a question of power.

Essentially energy/free champs have a small advantage early game, but energy users have a big disadvantage late game. Late game most champs mine as well have cost free abilities with how mana scales and they have better itemization *and* their abilities are often more powerful.