RE: Is modeling becoming too diverse?
R/C, which I believe makes up 90% of the membership in the AMA at present and likely makes up a similar ratio amongst all who fly model airplanes, could maybe be looked at lacking diversity today. Go to the flying field and count how many airplanes aren't ARFs and don't look like cookie cutter copies of each other! So, while some aspects are diverse, other aspects of the sport are increasing in their lack of diversity.
When I first joined the AMA, CL and FF were still major contenders of the membership making it more diverse then it is today and I think model aviation was stronger for it. Since I've dabbled in most aspects of this hobby, my interests are diverse and that makes me happy!