X Factor Deuce was one of my favorites of all time. The Z-Diff was in the .019-.021 range, and while Accu-tread was an aggressive cover for the time, it wasn't a grabby cover by any means so it was very versatile. Older balls I found that were very close to the Deuce in reaction and versatility were the Ebonite Mission, Ebonite SR-300, Track Kinetic, Black Widow (probably the closest).
Something that you could still find pretty easily that might be close would be the Jet Black Taboo, Track 505 C2, or Columbia Ransom Demand. They all have enough core that you could tweak layouts on and see a dramatic difference, don't "spin up" midway up the lane when the lanes break down, and maintain a strong-smooth roll down the lane as the pattern transitions.