Tack “&udm=14” on to the end of a normal search, and you’ll be booted into the clean 10 blue links interface. While Google might not let you set this as a default, if you have a way to automatically edit the Google search URL, you can create your own defaults.
DDG has had cost issues with some of the more complex queries. Exclusions (-) for example are very expensive, as Bing recently raised their prices. I think this is why search has gotten worse with DDG recently.