CJ,,,
Here are the pics of the DuckSlide I promised earlier... I think that you might be on the right path with putting a ramp on the back half of your feed block and feed tube... You will notice in my pics that the back part of the ball drop is ramped... I also do not use a return spring and can feel when something is not right and it stops me from pinching a ball... Most of the paint in the south east region has been running small as well and I only use premium paints when I play big games (i.e. Valken Redemption, RPS Premium, Ultra Evil, RPS Marballizer) outlaw games I have been using Procaps Visible Impact Pro or the left over big game paint...
DuckSlide in the closed position with the rear to the left side of pic
DuckSlide open position with 2 balls (one in chamber and one sitting on top),,, left side of pic is still rear
another view of 2 ball stack with left side of pic to the rear
Looking down in the chamber with one ball,,, left side of pic is the rear
I hope this somewhat helps...
WK2