Hm,well lets see. Gimp is complicated at first but once you figure it out. DEAR GOSH! What kind of creations will you make? Lol well it is tons of fun! I use it to draw many pictures. I think you should use the select tool that is in a loop,it helps wonders with coloring,the brush of course! The smudge and blur are also very great tools. Oh and the spraypaint is just gorgeous! In gimp,you can also create animations. Here is the creation I just finished,:

That,my friend is just an example,if you want I could probably teach you how to make animations. c=