I haven't read the entire thread but I'll give my worthless 2 cents.
I'll go through every character since it's easier to organize my thoughts and opinions in that way.
At the beginning of TO we were given a chart of which characters are supposed to beat which characters. This was Power>Sense>Charm>Magic>Power. In today's version, this is certainly not the case in the everyday PvP.
Lion-At the moment lion's are only made to beat mages. Sure they can try and break a powers guard or kill a pure buff but it's extremely difficult in todays version of Trickster. Lion's are glass cannons with not enough fire power, they desperately need a major ac buff or some defensive skill which can take on charms.
Fox-One of my new favorite classes to see in pvp, surprised at just how useful they are and completely different play style. Foxes are lethal against mages and sometimes charms but still need enough money invested in them to be able to not be 1hko'd.
(I don't know much about magic classes other than the Dark Lord and Light Mage so I'll stick to those)
Dark Lord-Perfect against powers and charms although need a lot of money invested in hp items. Can be taken down with a pure bunnies Flaming Fist though.
Light Mage-What can I say. Attacking skills use MA and so does their HP in a sense. When one stat benefits two like using MA for skills and a HP shield, that imo is OP. Light Mages can take anyone on except charms in some cases. Rust cripples powers and hinders charms, they just need enough lk to take on foxes and lions and they're set.
Buffalo-One stun skill which can usually win a match all by itself, hit rate is not bad though. Crazy AoE wind skill that can take out any Light mage or any character under 150k hp. Pure Buffalo's have no guard but still excel at dealing high random damage to unguarded characters.
Bunny-Great for 1v1 situations. Bunnies in some cases are good against every character in the game which is pretty OP. Here's the thing though, Bunnies are glass cannons. If they haven't beaten you in the first 20 seconds they're probably not going to beat you. Rust cripples any power (if they don't use FF) and it's a range attack so it's easy to use on powers. Flaming Fist is great for unaware dark lords but like I said, any smart mage uses rust and it's game over.
Cat-Sumo is a very hard skill to beat combined with tons of HV and HP. What's better than one skunk ability? Two skunk abilities...I'll get more into skunk on Racoon. Cats are great against everyone with the right equips although Powers and dark lords might give them a hard time.
Raccoon-Ah my favorite class. /sarcasm Let me begin with their OP stun kills. Full House, Impelling Rage, Power Charging and Skunk all in one way or another stuns the opponent. Unless you have a sprint there's no running away from that chain of stuns which imo is way OP. On to skunk...Skunk Pouch has a cooldown of 5 seconds and the duration is 12 seconds, how should that make any sense?! A constant stun that works for 12 seconds is way too long and way too frequent.
If I were to rank which chars are the most overpowered I'd always come to the conclusion of this.
So I'd consider characters who can beat any class as of today as overpowered. The reason why I ranked Bunnies way lower is because they are not built like a tank like the Raccoon and the Light Mage.