There's a lot of potential in the concept, but I don't think you really thought out the rest. First and foremost, the experience curve is ridiculous. I could be grinding battles for years and never level up. This is especially important since stats seem to dominate the game. I know you want people to play your game, but if people don't really feel like their effort is worth anything then the game's not worth playing.
Plus, I don't feel like all the elements of gameplay are covered in the tutorial. I would've liked to know if moving into my allies hurt them beforehand instead of figuring that out for myself. On that note, why is it that when you move into your ally, you either just damage them or push them depending on what seems to be chance. I don't know if that's a bug or part of gameplay, but if it's the latter then it needs to be explained.
It's really the small details you have to fix. Bouncing off the SHADOW of the terrain and not the actual terrain really messes up coordination. You get used to it, but sometimes it's just a nuisance.
The challenges are actually well thought out, but with your characters not being able to level up at a reasonable rate, they start to become impossible as the enemies just start doing obscene damage. The damage is actually mostly elemental, because the challenges cut your resistance to a flat amount, making resistances essentially useless. Try just reducing the resistances instead of bringing them straight to -50 or -100.
This idea of "billiards rpg" is pretty neat, but an innovative concept doesn't make up for lack of development.