Well I have some idea for a class, I would love to use this class, but I don't know if they would be allowed or if they are overpowered.

Mount Based Tank Class - Magic Version: Dragon - Tech Version: MechaVehicle
This class is a mount that is playable by players. This means it can be used to move around very quickly, and can transport other charaters with it. They also would be very durable, resulting in their tanking abilities. They would be a bit large, but not completely to scale that it'd be hard to see other players around them. They'd also have collision detection, so that the middle of the battlefield doesn't get too crazy. The end result is, everyone is trying to kill the dragon, so the wizard on the team can get hits in. Perhaps the PC mount will do run bys, have the mobs chasing it, perhaps it'll just sit in one spot and park, saying bring on the pain. Perhaps it will act as a mobile turret, where ranged characters can sit and concentrate on attacking, and not have to worry about moving or protecting themselves. It would be a new playstyle, and a very different take on moving through the world that could be quite interesting

Incorporeal Summoning mechanic Control Class - Magic Version: Incarnate - Tech Version: A.I.
This is a class based around the idea that the character doesn't have a body. They are incorporeal, and may travel the world in that form, able to communciate, but not able to directly affect much, but provide recon and simple healing/repairs. There would be an ability for them to fuse with NPCs, whether they be monsters or robots or thugs or what have you. In this way, the Incorporeal character would be able to remove that NPC from the fight as well as use it as a summon, until it is destroyed, or the effect/manifestation/hack/possession wears off. Bosses would be pretty much immune, but perhaps they might leap into a mob in a group and begin taking out the foes from within. Perhaps they might scout ahead/around and find all the goodies and baddies on the map. Or perhaps they would hop from mob to mob, leaving them stunned for that moment as their teammates attack. Or perhaps they'll take the time it takes to hack into/break a miniboss and use that character to join the team. Perhaps they'll even fuse with a character, which would double that character's mana and regeneration and both players would be able to use that character's moves simultaneously (making them doubly effective). In any case, it'd be a new playstyle that revolved almost entirely around what enemies they were facing.