I don't think the gritty/old timey look is bad, but I think you could push it further to sell it as such. I think you could go a long way by adding SOME saturation back into the world, and tinting things a bit sepia for an aged look. I'd still leave the bullseyes full saturation, though, as they really do pop right now. If you want to keep things feeling deliberately old timey and worn, adding a little bit of aged film overlay would go a long way (some decent examples of this type of aging, though fully black and white instead of just partially desaturated, can be seen in the games PB Winterbottom or Limbo).
Out of curiosity, what led to the bullseyes being spherical instead of cylindrical?
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PB Winterbottom http://www.youtube.com/watch?v=qMZyAsVlMoU#t=1m10s
Limbo: http://www.youtube.com/watch?v=GCA79zPaQe0#t=30s
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Edit: I got distracted for a bit but here's a moderately quick mockup of some of those ideas:
http://www.meltwizard.com/stuff/factory.png
You could make people "feel" the gyroscopic movement even more by having the UI's movement be slightly delayed from the player movement, like it's following behind on a rubber band (see: first person games which have helmet art, like Metroid Prime on the gamecube). You wouldn't want to make it too crazy since it has to be usable, but adding a little feeling of sway to the surrounding chrome, tied to gyroscope moves, would probably go a long way towards making it feel less mechanical and more fluid.
Sorry for the armchair art direction by the way. If I am accidentally coming across as an asshole, please know that it is not intentional! I like the concept for the game AND for the visual direction and it made me interested enough to crack open Photoshop and start playing around. I don't know if my ideas are particularly noteworthy or if they actually manage to improve anything, but it's what came to mind when looking at the game. Hopefully no offense is taken!