I like this and it's functionality. We would prefer no shadows, if you think that will still look good. As for the logo part; what about a set of gears or something mechanical?
Entry #19 is great. One concern that I have is that the orange may get drown out if the sign is on wood. Would another color work well with the blue and grey? Otherwise incorporate more blue/grey?
Would it be possible to remove a few "spokes" from #29? We are thinking we would like something less busy. Maybe remove every other one, or more? If that doesn't make sense please let me know. Thanks!