55k with 3 effects

I created 180 x 150 ad with 3 effects, FESAlphaBars, FESSlide and FETSpiral and one image.
I optimized it and published it. The file size is 55k and I think it is too big.

Can I do anything else to minimize the file size?

It is possible to get to that size since the FlashEff component itself has over 20k in size. And there's also the embedded text for the text animations. So there's not much you can do to lower the file size. Just check to see whether you have any other objects in the Library that you are not using and remove them.