Something to keep in mind when making flash games or even any other indie games, is that they are going to be smaller than a proper console/pc game wether you like it or not. So instead of fighting the urge to expand on everything, sometimes it will make more impact with small cute characters and graphics. Sometimes smaller is better if the game is small. Theres no point having over done realistic graphics for a simple cute platformer. It's overkill. So don't stress out and try aim for smaller cuter things when starting out and leave the realistic tough stuff for when you tackle a big game.