Here is a nice little paper describing lots of things related toPSC motors.
http://www.ece.wisc.edu/~lipo/2000pub/00-04.PDF
Namely how capacitors are selected and that the AUX winding has a higher resistance than the main winding. Now, I'll bet that you don't have the ability to do 4-terminal ohms measurements on your motor. I have a few meters that can. 100 micro ohms (0.0001 ohms resolution for resistances below 200 ohms using a 4-wire method.
That real-word example shows 8.69 ohms and 9.91 ohms for the windings in the article. Without a 4-wire technique, your barking up the wrong tree. In that example it differs by about 12%.
The motor theory says that the aux winding has to be higher because the LC circuit of the capacitor/inductor circuit raises the voltage potential required to get the same current in the main winding.
Furthermore, it makes a reference to pulsation if you don't tget the capacitance right and you generally have a small range to work with. So, too much and it's going to pulse noticeably. To little, it may not be able to start.
And yes, changing the winding that gets the capacitor can work to change the directions when the windings have similar characteristics. Reversing either winding will also reverse the direction when the windings are identical.