One of the things we have not discussed is the variation from the measurement process. Have you performed a gage R&R to see how much of the variation - or even the fliers - come from the measurement itself? Both the measurement and the process are very "organic", so it would be good to sort out each one's participation.
A key to any statistical evaluation is
total variation. Your data represents all variation - not just the variation of the process. It is always a good reminder to consider that when we look at data.

Your process reminds me of the old days when I molded carbon fiber/polyimide composite aircraft engine bearings and components. Ah, those were the days.... Do you look at cracking (in addition to porosity) as a participant in the voids, too?