This is probably a stupid question but do the wallpaper sizes you asked for allow for the multiple-home-screen sliding of Android to work? They're the same size as the devices' screens, and I don't know if that means that it would only be big enough to cover one home screen without being stretched, or if Android does something differently with regard to setting wallpapers.
Also, the Hero boot animation is 217 frames long, does this matter?
And finally, I guess the animation should be able to loop (?).
HTC Universal, HTC Monet, HTC Touch Pro, HTC Dream, HTC Hero, Motorola Milestone
LG Optimus 2X [CM7 with stock launcher and ironkrnl]