I personally think the F Major Suite, BWV 809 is the easiest one and the D minor Suite, BWV 811 the hardest. But all of them are much harder than the French Suites. If you're coming from the 2nd French Suite, I suggest first learning Maybe the 3rd, 4th or 5th before moving on to the English Suites. If you're ready for them, I'd start with the F Major Suite (Nr. 4)
BW,
Marijn