little update.. I threw some rearrangeing code together in the last half hour.. the results aren't too great with the current system (although using a new one won't be bad.. I can reuse most of the code)

A few randomly selected sheets: http://www.princeton.edu/~mspear/jj2/

I don't think I'll be able to keep 1 sequence per row and same space taken up per sprite, as some sprite sheets get HUGE (jazz=50MB!, all=~250MB total).. I'll probably just switch to closest packing or something, but I'll try a few other things including a batch PNG or GIF conversion...