HEY!!! no background can be a good background!!!!
if there is one thing i would take from the troll that you should prolly take care of or get like troll repellent or something, its the lighting effect. (i wouldnt put it like he said it cuz that was a douche thing to say) but the spotlight effect would look a lot cooler for something like this, leaving your background black on top of the spotlight would leave a very interesting effect. it would also bring attention to your characters a lot more (not that im not lookin at em lol)
i like your coloring but careful with that burn tool dood, it looks sweet on the cloth, but the bass drum doesnt look as blended as well. for a situation like that id use like the blur tool to soften the edges of the burn (try it see if it looks a lil more blended, but thats photoshop trying things to see how they look lol)
also try doing some drawings of real life too, its boring but can be fun sometimes, like see if you can get one of your friends to be a model for you and do some figure drawings. its always good practice to draw from real life, and it also helps you learn as you continue drawing cartoons. Human anatomy does that too so pay attention in anatomy class! lol yea you're willing to stick with it and have a drive for it, and for portfolio purposes its good to start doing figure drawings anyways! later days!