Bugs, Balancing, Content
Great experimental game. The idea is really good, I had the idea of a RPG-style mage like this in a jump'n'run game before, but never got to get it made.
I had two savegames at levels 11 and 5, saved as game 1 and 2. Now, game 2 is game 1 and the level 11 mage is gone. The saving system is not entirely fixed.
I played with a pyromancer and the game was quite easy. I tried a frost mage and it was a bit more difficult. Standard shots consume so little MP that you can almost outregenerate it. I never had MP problems, nor was I ever seriously injured. You can win the game by NOT killing stuff. Runnin speed upgrades aren't really felt.
As I said, the experiment is a success. Now make a game with more accessibility and more content, a real story maybe. The replayability value of this version of the game isn't going to make me finish my second character.
I have to oppose the general level cap hatred. A longer game could feature some kind of respec, but still, not being able to get everything is a key aspect of the gameplay. What you could do, however, would be to make an experimental mode with no level cap but no skill point cap per skill - after all, all (most?) of the skills were formulae with arbitrary limits. Of course enemies would have to become stronger and stronger.
Oh, elemental resistances. Nothing says "I'm a well-balanced magic RPG system" more than an actually weak enemy that you can't kill with your fav spell so it shifts from "actually weak" to "kinda strong".
I'd appreciate items, quests, different towns and the such. You know, I like the game mechanics a lot, but I think there is that much that can be done with it.
Final thought: triple fireball is epic.