A few problems...
It was too much like the original, not enough new features to be impressive. Also, there were some platform issues, like I passed right through a platform when I expected to land on it, some "hitbox" issues when I clearly hit an enemy with a weapon that should kill and they didn't die, causing me to get hurt. My two main complaints are the horrifically repetitive music and the tail-whipping... most times, the tail-whip animation got stuck with the monkey's tail extended, especially if you double-click the tail-whip button. Also, the tail-whip nodes didn't seem to have the kind of detection I was looking for... basically, if the very end of your tail didn't hit it, you didn't latch on, which caused me to die a few times. It makes sense in real life, but this is a game, give us a little leeway. The music I realize can be toggled on/off, but why put in the music if the player is just going to immediately turn it off?
Another exploit I found was if there was a level that contained a new weapon, you could just die and reload, get the weapon upgrade again to unlock the next weapon, as the weapon just unlocked was still available.
Finally, the wizards were a nice addition, but they were bad enough solo... if you pair them up, most of your time is spent trying to dodge lightning and fireballs rather than killing your enemies.