I like how Orianna, a "utility" mage outdamages Viktor
I don't know when people will realize Orianna has been consistently one of the best mid laners in the game for years (come worlds she'll become popular again like she does every year) but it's still bullshit that she goes toe to toe in damage output with other damage mages while also offering a huge amount of utility for her team.
Karma is balanced like a utility mage (actually gives up damage for utility), Orianna has gotten the best of both worlds for a long time now and I hope Riot tones her down eventually.
Edit: If you really can't see why Orianna is the reason for the lack of mid lane mage diversity i don't know what to say to you. Take basically any immobile mage and try to list of reasons why you might want to pick them over Orianna and then when you realize you can't you'll understand why she needs to be nerfed.
Orianna straight up offers more utility and at least matches the damage of half the mage roster in the game. She's the invisible renekton bar of mid (only because she actually requires some skill to play with unlike renek) and needs to be nerfed in order to increase mid lane diversity.
Anivia isn't that strong, I guess.
Tons of stuns, flash-tibbers engage is faster than an Orianna QRW.
Tank melter. Passive + Liandry's is pretty strong.
Ridiculous DPS.
He's tanky even if you build as a mage and makes a great anti-assassin pick.
Not really super strong, but his ult is amazing if you can play him well enough.
May actually have better zone control than Orianna.
Honestly not that dangerous.
Snare, AOE damage, shield, laser. They're about the same in terms of damage and utility.
Silence and suppression, insane single-target burst.
Stuns for days.
Very high single target burst and is extremely powerful when played well.
Not that strong, but he does have that "infinite scaling" thing going for him.
True damage procs, so well balanced that he has quite literally never been changed except for clarity (except when they gave everyone 4 armor).
Very high damage, both single target and in groups. Also has better disengage.
Not really all that strong, but he has really good range and mana sustain.
Lots of long-range poke.
Less zone control, but more hard CC.
's abilities combined, and only 25% less AP scaling (her passive not included).
is a utility mage whose ult can deal a crap ton of damage