I revamped some of it using some of the suggestions, and finally got it under 5lbs! (4.99lbs, to be exact) I've been trying to do that for two years, and this is definitely less sketchy than some of my other attempts.
The top support clamps onto the CIM with set screws, but the bottom uses a plate to support the CIM and directly interfaces with the bearing. It's a much stronger connection. I also upgraded to a 30t gear over a 24t gear for the turning gear to reduce the backlash a bit.
That being said, I'm still not sure I would use this for most competitions, or at least not without a couple extra pieces. The most sketchy part is that I had to resort to using a press fit to hold the large bearing in the gear. The thrust loads are all opposite the press fit, so theoretically this is 100% ok, but we all know how theoryland is deceiving.
The most dangerous parts of this are the small bevel gear shaft bearings, and the press fit. Everything else I feel fairly comfortable with.