After several years of acquisitions and testing new ideas, I own a tangled mess of overlapping sites within the same segment. Looking around to see how to simplify, I've noticed competitors using several different strategies...
1) A network of doorways...mostly generic domains that pertain to a subsegment ("bluewidgets.com"). These pages pretend to be separate sites, but all navigation leads back to a central site ("widgets.com").
2) A network of fully functional subsegment sites ("bluewidgets.com","purplewidgets.com", etc.). I have seen competitors with multiple sites in the top 10 search results for very competitive terms, despite duplicate content.
3) Focusing exclusively on one site for the segment.