Really hard to associate movement with the mouse.
It took a lot of mental effort to make sure that I was dodging with my mouse and aiming with the keyboard, especially with the movement reticle that makes you think it's an aiming reticle. I think it would have made a lot more sense to do it the other way around, personally, and that way you could aim in 360 degress also, or at least get rid of the movement reticle and have the movement almost directly pertain to your mouse movements.
I kinda got used to it, but it screwed with my brain and made it too uncomfortable to play for very long.
Other than that, it seems very well made. I hope it does well.