My thoughts on Mages.
I'm going to simply break them down to four categories for Solo Queue, and why I see them the way they are.
Great and still very much alive.

Generally speaking, these champions do very well into assassins (as we can see with the win rates for the most part across the board).
I was caught between putting Anivia in this group or the next group. I put her here for a few reasons. One being her waveclear is unparalleled, even with Riot trying to nerf waveclear this champion's identity is Waveclear.
TF can bypass the whole danger area of assassins when ganking bot lane, I mean a lane...
Vlad can pool out of danger so long as he does it before Ignite would have killed him. He also has a very good laning pattern for dealing with assassins.
Zilean, has had a high win rate for a while now. It has a bunch to do with past meta and current meta being fit for him. The one tricks are doing very well.
Xerath, is generally always in a very safe area. I don't think Xerath is ever really a bad pick. Might not be the best pick, but never a bad pick.
A Sol, is again generally played by one tricks, but A Sol has the tools to force assassins off of farm and roam properly before a assassin can. His roams are also able to be much safer than most other mages. So he isn't threatened by assassins sitting in a brush waiting for him to roam.
Karthus, has a crappy lane against assassins. But can be completely mitigated by good play. His late game will always make anyone that is not a tank cry. He also doesn't care if he dies in the late game if that killed two people. Generally speaking though, one tricks doing very well on the champion.
Zoe, I'll be honest. 8% play rate with a 51% win rate. I get it the win rate isn't that great, but when compared to everyone else. She is the highest play rate champion with the highest win rate. Followed by Vlad. So she seems to be doing pretty alright. If we were to swap this over to strictly the one tricks, she might have an even higher win rate.
In relatively good shape and can still contribute a bunch to a game.
(not sure if we should call her a mage?.. Always actually wondered that myself)

Ekko, is very good into assassins while being able to fight them fairly easily as well. His roams aren't the greatest but overall still very strong.
Malzahar, is still a good champion (even though he is the most frustrating champion to play because his lane is ass, not gonna get into it). He is able to lockdown assassins while they beginning their combo's. Anyone and everyone in flight is knocked down and suppressed. Assassins being forced to get a QSS early in the game kills the assassins extreme strength. Doesn't do very well into other mages, but is always useful to the team.
Ahri has me questioning if she requires some buffs, since she feels weaker than how she was. But that could be that people aren't used to having the movespeed taken away from the Q. But in a general sense, she is able to poke out assassins while being able to deal damage. She is fairly safe and is able to reposition as fast as assassins (Maybe not Kata, or Akali. But pretty fast).
Cass, has a few tools that allow her to kill anyone and everyone. Her W is a natural counter to majority of assassins. Her R is the "Oh Shit I missed my W" button that allows her to kill assassins that come flying at her. Still does VERY well into other mages.
Orianna, is a niche champion that will always shine. There isn't going to be a time where Orianna will be weak. Unless Riot decides to increase all of her mana cost to real numbers. Aside from that, Orianna will continue to have one of the biggest bubbles in mid lane (at a solo queue level).
Liss, very good for locking down assassins and staying alive. A bit weaker than Malzahar, but much more sustainable than Malzahar. But to be fair, she needs some looking at. She is mainly played by One Tricks.
The playable and has decent success, champions.

These are champions you play because you either want to play them, and feel very confident with them. Play them because they are a few champions you know how to play mid. The offer decent tools for your team, but not really anything that isn't offered better by someone else or another item. These are the champions that can still perform and put in work, but the payout generally isn't worth the struggle. I recommend only playing these if you are very confident with your ability to climb with them.
The Don't Think About Playing Us, Champions.
Yes, we finally made it. My home bois. This is where I belong.

These champions have either been nerfed so hard due to professional play, been shafted by meta shift, or have been outclassed by a combination of both. That the reward for playing these champions in Solo Queue is near none until you get to a very high elo and even then, some of these champions may not do well in high elo. (Looking at you Azir..)
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