I just had a play its really good and has a great range of play and enemies. Just feel it needs to ramp up a bit speed and challenge or maybe score requirement to keep playing.
The rings look and work well but I thought you were meant to jump through them? seem to score just from hitting them. This kind of makes the jump redundant so as part of the random spawn of the level should have some rows of rocks you must jump over.
When I died I bounced on several hazards this was a very nice touch.