Having just released
Rocketbirds: Revolution, an in-browser Flash game for which I did the majority of the background art [/shameless plug], I figured I'd use the down-time to start mocking up a shmup based on the characters from that game, and specifically, the circumstances in the intro. I haven't really figured how I want to handle the background (ie, whether to go for simple, parallaxing silhouettes, or something more detailed a la Aero Blaster or UN Squadron). So for now, the background and sky are somewhat placeholder.
For the sprites, I still need to go in and rejigger the palettes, since I did up Hardboiled (the chicken) with largely the same palette I used for the penguins (and you can clearly see the difference in color focus between them). Right now I'm also trying to sort out the working files, since they're a bit of a mess of layers (am I the only one that's underwhelmed/frustrated with how Pro Motion handles layers?). I'll likely have separate sprites for arms/weapons, body, jet plume, and the lighting from the muzzle flashes.
Style-wise, I'm more than likely going to stay away from any AA, except possibly some local buffer shading if absolutely necessary.
Not sure where this is gonna go, but once I get a few more assets together, I'll probably start prototyping in Construct. Whether it goes beyond prototype will depend on the bossman.

different weapons and orientations (for movement around the screen)

and a quick animation test

Any c&c is more than welcome.