Good Sprite Animation Programs?

Greetings, Midday here.

I recently found Photoshop to be less useful for sprite animations than I previously thought, and I've long since abandoned using Flash for sprite animations except as a compiler for exporting as .SWF. I usually make my animations in Photoshop, then export them to Flash and compile them in Flash. But lately I found that Photoshop doesn't really do what I really need in making sprite animations--it's lacking in shaped motion paths, which is like, really important if I ever want to do something like fake gameplay vids of my planned fan games or for my planned original games that all use sprites.

Which brings me to my question: anyone know of good sprite animation programs, besides Photoshop and besides Flash?

I need the following features in the sprite animation program:

* motion tweens
* shape motion paths
* auto-align to pixel grid for sprites in each frame of animation
* able to be exported as .PSD, .FLA, or .SWF or other file type supported by Photoshop/Flash

Some features that are preferred but not necessary:
* able to add audio tracks or sound effects
*  able to alter the speed/acceleration of objects that are on the shaped motion paths without having to do it manually frame-by-frame

I am willing to purchase such a program if it's the best animation program out there, but otherwise I'd rather have something completely free.

Basically I'd like to get an animation program that can make stuff approximating SNES-quality animations or GBA-quality animations.

Help would be much appreciated!