Still hesitates off throttle...

Well, yeah, the accelerator pump spring's tension ought to be given some thought every five decades or so, whether it needs it or not, LOL. I routinely stretch 'em a bit before reinstallation.

You might have crossed over from not enough of a pump shot to too much of a pump shot, or you might have more than one cause of the hesitation and your pump shot adjustments are addressing one cause but not the other. There might be something still to be found in the distributor…

…errrrr, yeah, hold on a sec. Going by your screen name, you've got a '68 Dart. Those came with CAP, the Clean Air Package, which was the auto industry's first effective exhaust emission control system. Is your car still equipped with the vacuum advance control valve perched atop the cylinder head, just to the driver's side of the valve cover, about 3/4 of the way back? Fat hose to the № 6 intake runner; thin hoses to the carburetor and distributor? If so, that needs to be working properly and adjusted correctly. If not, you'll have great difficulty getting the engine to behave nicely for you. As described in the linked article, that setup is intended to have very retarded basic timing (around 5° ATDC). The distributor is configured to kick in a bunch of mechanical (centrifugal) advance just above idle, and there's a long-throw vacuum advance. If you're running a CAP-curved distributor without the valve and/or with the base timing advanced a bunch of degrees from spec, then yeah, the car will run reasonably well with the vacuum advance disabled (but not as well as it could, and with increased fuel consumption) and will exhibit weird driveability faults with the vacuum advance enabled.

Good options would be either to put the system the way it was built, or recurve the distributor to non-CAP specs, or kill multiple birds with one stone and do the HEI upgrade (which involves installing a new distributor, and the electronic distributors did not have the unusual advance curves found in the '63-'69 CAP distributors).