Interesting, but widescreen would be the last thing I'd be excited about from the engine. Forcing these old 2D games into widescreen always gives you an advantage that was originally not there.
Being able to see further around you might be convenient, but also very different from the original experience.

And how does the engine handle the original behavior? Enemies started moving only once they were visible on your screen, projectiles did not fly much farther either, points and pickups dropped from the sky only once you were in vision (was often used as secrets where you had to jump from the highest point to get the camera to move so that the secret pickups would drop) and much more. Has all that been adjusted? I seriously doubt it would be a 1:1 re-adjustment for widescreen.

But either way, as widescreen is only an option of the engine and you can keep the original 4:3, you can ignore all of the above.

Everything else sounds really good. More sound channels, easily customizable controls, quick save/load. Love it.

Now only to make them re-release the Duke games on GOG :P