driver's window doesn't work all the time; sometimes it rolls all the way down, and only comes up an inch or two every 3-5 minutes (bad news when it's raining, or windy)...
Passenger window doesn't roll down at all...
...have had the door panels apart multiple times - checking wiring, switches, etc, and find nothing out of the ordinary - except they don't work correctly. 'have consulted the shop manual repeatedly and find nothing to help...
ANY ideas will be greatly appreciated.

Unfortunately, your window motor needs replacement.

Unfortunately, your window motor needs replacement.
I have recently discovered I have this same problem with the window motor, but upon opening the door panel to find the motor discovered this may be tough to change. Is there a special way to get this motor out, or is it a job for the pros.

Getting the motor out isn't too bad, provided that you've got a cut-off wheel, and you'll need a rivet gun to replace the motor. (Don't try nuts and bolts - even with super strength threadlock I've seen nuts and bolts come apart.)

You need to cut off the three(?) rivets holding the motor in place. Support the window with some tape or a bolt through the regulator gear and frame. Then the motor just kind of pops out, you may need to move things around to get it out, but it will make it.

The new motor just pops back in the opposite of removal.

RIVETS RIVETS RIVETS.

Hope this helps.

Cut off wheel? I never used a cutoff wheel to remove my rivets. Just take an electric drill with a bit that will fit in the middle of the rivets and drill away. They come right out.