I'm working on this one right now. I have finished the bottom ring and the fins. While doing my dry fit of these parts, it occurred to me that the pieces could be split a little differently to make it easier to assemble. The fins and central ring could be printed as one piece and the outer ring as another.
Another possibility is to include the fins and inner ring as part of the main body. Of course this way would only work for people with large printers.
Great design however, great job.