I'll jump on the bandwagon also.....
I drive a 95 Avenger with the 420a, I have the exact same hesitation problem. Non-turbo, automatic. Here is a list of the work I have done (personally) in the last while, also I have had this problem for upwards of a year.

~just replaced coil today (no output on #3)
~MSD wires are less than 6 months old and check out good (ohms)
~new plugs today also
~new top end gaskets and rebuilt head (timing belt broke)
~changed out injectors today (another used set)
~checked voltages at TPS, good
~checked voltages and heater in the O2 sensor... voltages seemed screwy, all over the place... from 200mv up to 800mv's at idle (normal?)
~going to change fuel filter tommorrow, it needs it anyways
~NO CEL, ever, yes the bulb works (unless i unplug a sensor at idle)
~plugged EGR system, no change
~also changed MAP with another used one, no change

I want to check out the fuel presure during driving, and see what happens, anyone else do this yet? If so what are your findings?

One odd-ball thing I noticed was when I was checking TPS voltages, I was hearing a buzzing sound (continous, never changed), the key was ON and engine was OFF. I traced it to the ECM. The ECM is buzzing... this can't be normal.

I did drive the car with the O2 sensor unplugged, (open loop?), and there was no differance at all! I am going to replace the O2 for $hits and giggles.

My hesitation/misfire problem is the same as all of you have described pretty much. I can get to WOT if I ease into it, but if I get on the pedal fast it bucks and farts, backfires through the intake, huge power loss. The problem doesn't seem to be as bad over 3000 RPM, but the more load the worse it is.

Check your ECM's with the power on and engine off to see if you can hear anything......

I'll be keeping an eye on this thread and I will post of any changes/repairs.

Steve