This is great stuff, but I wanted to report a couple issues with the mouse that makes this frustrating to play:
1. Occasionally (and very frequently when using a keyboard key, and even more frequently if holding one down such as Tab) the mouse cursor will momentarily jump to the top left of the screen, causing your ship to turn up and left even if you're using a joystick. It appears what's happening is the mouse is jumping to unscaled window coordinates, as if it was only in a 320x200 window.
2. At the start of a mission, the mouse starts by default all the way down and to the right, causing your ship to spin around wildly in circles as soon as you launch until you center it. Also very annoying if you play with a Joystick. It should start centered instead
3. The mouse is not contained to the game window, so if you play with a mouse on a multi-monitor setup you frequently click outside of the game, minimizing it.
4. Occasionally, alt-tabbing out and back causes the window display to be lost forever (stuck on black or the previous frame before switching)
If it helps, my OS is Windows 8.1