I plan to upload the actual sub as swf, so people can zoom in, but the file size is still too big (around 800kb). Any suggestions?

I really like this, not really sure what else you could do with it to make it better. Could you maybe upload it somewhere and provide a link so that we can see it in a bigger size/better quality.

I'm trying to see if I can replace the large blocks of text with some smaller diagrams and charts for some variety.

How about a colored version?

maybe make the text look more like hand writen notes.