I'm trying to avoid US based search engines. 'Startpage.com' utilizes Google (officially) and anonymizes the user access (towards Google). They sit in the EU (Netherlands), where strong data protection laws are in place. They are in business since 1998 ("Ixquick"). So what are you waiting for? What is your problem with not adding them to the default list?
They do their job damn right and the results are equal to Google.
I'm quite close to drop the use of Opera again, since I always forget to put the shorthand letter prefix for Startpage.com in the URL/search box and that ugly (another US based) DuckDuckGo pops up unexpectedly. Well, or whatever search engine Opera "allows me" to mark as default.
Security driven measurements against rogue default set search engines is a good idea, but please keep up with the available search engine options on the market!
Hopefully you don't have a personal beef with them, your users now have to pay for.
Or is it a Norway vs. Netherlands thing? Hopefully not.