Too much cam?
Okay lets try looking at just the hesitation first. This could be caused by your secondaries opening to early or too late. Process of elimination try locking the leakage on the vacuum secondaries so they can't open at all then if the hesitation is gone you know that the secondaries are opening to early and she's going way lean (I think). Now obviously it ain't going to pull worth a dam but we are only talking of off idle hesitation. I had the same problem and cured it with a double pumper but my engine is completely different than yours so it ain't a fair comparison.
Terry