Being a good reviewer is an equally important skill so, if you want, practice on that ;o). If you manage to give the artist a detailed review of what you thought (as a viewer or listener) was good or not you are helping the artist evolve much more quickly into a whole new level.

Your bro is really good, btw, and I hope I can learn from his creations. Who knows, maybe you have the same skills running in your veins and you don't know it. Why don't you give music creation a try? There are plenty of demo softwares that let you create music (Fruity Loops 8 demo version is the program I use).

Cheers.
-SFaPiL