No idea if it's technically possible, although it really feels like it should be, but for me the biggest single improvement a site could do to animated gifs would be to allow at least basic video controls - particularly pause or step backwards.

I hate watching a 30 second animated gif where the fancy skill or whatever that it's trying to show is about 2 seconds long and I have to keep looping round and round again to try to catch the critical moment.

Maybe it's already out there somewhere, but I've not seen it.