Mark, wow and flutter are persistent problems with the older, pre dual-speed mechanism.
Soem things to check:
Make sure the turntable shaft is thoroughly oiled. There is an oil hole atop the casting where the T-T shaft assembly goes through.
If the machine has sat idle for an extended period, the belt will develop a "elbow" and cause wow.
Make sure the two rollers on the fork that retracts the turntable pilot clears the flange while in the play mode.
Check that the T-T motor worm is not too tight as to cause backlash on the gear it drives.
There must be a ball bearing on the end of the motor shaft and held against the copper finger spring. Simple observation will do here.
In some cases a too-high tracking force can cause wow on warped records.
As for the "strain" this has long annoyed me. I solved it by stretching/weakening the two large springs under the deck that lift the record. The original force was bizarrely high, I aim for approx 5-7 oz on the 100-104 and around 10-12 oz for the 200's. You'll need a gauge with a approx 20oz scale and hook that can attach to the underside of the lift arm. With arm up in play mode, shut all power, unhook the spring, attach one end to a firm structure and stretch it to teh point where you feel a slight "give" (wear gloves). Hook it back up in the machine and test the pull-down with the gauge. Go slowly and expect to do it several times for each springs.
As for the strain on pulling back the pilot and releasing the record, there is no really easy fix for that. On one machine I removed the small bearing that rides the cam and used a slightly larger ball race bearing. this however meant that that arm now moved too far back and would slightly conflict with the lift arm. I was able to cut away some of the metal to clear the conflict and add an "S" hook to compensate for the need for a longer steel cable.
It reduced the strain on the mechanism...but added one for me
. On the old DC motor machines, it isn't really critical, just keep it well lubed.
Rob