Thank you Jason. I now remember that you had already investigated this route, as reported in the forum here.
It looks to be a mix of the Annular Electromagnetic Generator for Harvesting Ocean Wave Energy and the gravity device to compress air as shown on the video below (already in a previous discussion):
Pr. Seamus Garvey envisaged such a device for very large scales, allowing the weights to fall:
In a similar way, I expect your gravity device could better work at large scales. Perhaps you could replace the central annular generator with (for four blades) two tubes, each tube connecting two opposite blades, and including a coil at each respective end, and a magnet. The magnet falls from the top coil towards the coil at the bottom, at full speed, just like the weight falling in Garvey’s device. Now you would have a generator running in fits and starts, which may not be a very good thing. The annular generator as you envisage is surely better, and corresponds to the concept of the Annular Electromagnetic Generator, the difference being a regular rotation rather than the motion of waves.