Anyone interested in these kinds of game design principles should read "Trigger Happy." (Forgot the author's name.) It explores these and a ton more issues. Of course, the format is paper based... :-) Great book.
Very well done platformer. The sensation when you land on a spider feels just right. I'd love to see a map to find out all the nooks and crannies I missed.
I tried twice, but each time I only scored in the low 200k range. Am I doomed to mediocrity, or are there some tricks to doing well? For example, I found that shooting a low row of aliens from the bottom (where they can't shoot me) worked well.
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