Good, but you can still improve the game physics
It was pretty good compared to the latter versions, but I couldn't stress out much further how crucial it is to really get the physics of the game to work the way it should. I think the key to the success of a game such as this is a good balance and relationship between human intuition, perception, and game physics. The ability of the game to actually deliver the correct movements according to how the player thinks it would react must be taken into real consideration. In other words, it should be pretty realistic motion-wise.
Another thing is the AI of the opponent. But its doin okay so far in that department so nothing much to add there, but to improve it as much as you can.
Graphics and sound ain't much of a big factor here in my opinion, but it still does help make things way cooler.
Overall it was good, but it still can use a bit of improvement. Keep it up!