I hate to say this, because I am a BIG fan of DuckDuckGo, but I think your ranking algorithm can be improved.

I collect domains for my open source project, OpenDomain. The sites do not actually have too much valuable content - just placeholders so people can find them.

I just checked, and quite a few of my domains are listed very highly on DDG. Not that I am complaining, but I think they are rated high just because the keywords are in the domains themselves.

For example, "NoSQL", "JSON", "Free TV", "liposculpture", "WebPlatform", and "Helpher" all scored top hits for my sites.

I am not asking for my sites to be removed specifically, but we should try to get better results - I have done NOTHING for SEO on these domains - just owned the keyword.