In chatting with Adobe, one thing that came out was that their Ajax indicator (the spinning activity indicator) had not be optimized. Since this is just an animated .gif file, its an easy replacement.
Just go to \CFIDE\scripts\ajax\images and replace loading.gif with another image. You can get other indicators at:
Since they're just images, simply right-click on the image and save it down. Then drop it into the folder specified above.
You will need to rename your new image to loading.gif.
Then, clear your cache and reload your page. In my tests, doing this shredded 100k off of the page size.