Well, to be a graduation project this is impressive! You've done a lot of things right that are not easy at all.
The game is a pleasure to play, visuals and sounds are very good and works pretty well together.
I liked the level desing, even if some part are a bit rough (aka the fall with spikes that you have to pass with trial and error), but the chekpoints are close enough to make the difficulty just right for me.
If you ask about what could be added to the game it's totally up to you. Right now you have a good base to start with. You could add more platform mechanics, combat mechanics, quest mechanics... My only advice is to experiment with prototypes and see what's works better for you ^^
Overall a very solid submission! Also, I am a rat.