Regarding your end cap valves clogging, you didn’t say HOW OFTEN this happens. My ‘fix’ for this problem is to run hot water thru the valve after each use, dunk the cap in a small dish of isopropyl alcohol, then set the cap under an electric light to dry the alcohol. I also shake the cap to assure myself I can hear the valve is free and clicking.
However, perhaps my sessions are not as lengthy as yours or involve as much lubricant and/or semen.
I also have a good selection of receivers to choose from should one misbehave.
I recently went down a liner size with good results. Thanks to the originator of this thread for writing about it.