Hmmm... Macromedia Flash can have animated gif's imported and exported. And you still have all the options you can have with swf files - apart from the fact that the animated gifs will be a single layer. Which means you'd need to stick each frame into an image editor (copy the frame from flash) to be able to edit it that way.

And you can get ut as a 30-day free trial... which you can keep indefinitely if you know where to find the Flash entry in the Registry and just delete it every 30 days then re-install the program.