A wide variety of knowledge is needed here. Performance isn't a single thing. The way tires help performance is by allowing larger loads to be transfered to the chassis. You want to go around a corner fast the tires grip the road to their ability and transfer that force to changing the direction of the chassis.
This ability is improved with big, fat, agressively treaded, tires. The tires ability to do this also improves its ability to do every bad thing it can do to the chassis, including shake, shimmy, track, pull, wobble, etc.
The fact that anyone including MB has installed successfully monster tires is only qualitative. For every thing ones adds in performance one place, one takes away in another. The key for me is to see the way the car was originally designed and look for specific changes. The car was designed for 195/65R15 tires and no where in production did they change the things one would change if one were to change tire adhesion. The bushings are still the same the tierods and sterring shock are the same. The shocks and springs are different.
From the latest specs you show there is almost no compensation. The car should pull to the side with lower CASTER, but .3 deg is negligible. An attempt to deal with your problem has not been made within those readings, unless they are all that can be done within the adjustments. The 124 body has cams for CASTER and CAMBER adjustment and is limited in correction by the lift circle of the cam.
To understand CASTER look at one... the wheel on a caster rolls on an axle that is not underneath the pivot for direction. If one draws a line between the center of the axle to the center of directional pivot, one is scribing the angle of caster. Think of a grocery cart. You push it and all wheels line up. Every once in a while one gets a cart where the wheel is bent up under the chassis such that the axle of rotation is directly below the pivot point (zero CASTER). This wheel wobbles and turns around changing direction at the slightest.
Bosch Master, ASE Master, L1
33 years MB technician