Technically, the J-35 was a "double delta", but close enough. You're missing the F-104, also, but it didn't have an air-to-ground mission yet, so I'm going with the J-35 as the best "all-around" fighter/interceptor of the mid-60's. The F-106 didn't have an air-to-ground capabaility, either, and never did in it's 30-year operational history.