Excellent post Sir!
I myself discovered that HPA and regs don't like each other when temp is near or well below 32*F.
I also want to point out that balanced valves are not to be given up on.
A 40fps spread at 50 yards equates to 1/4" lower POI.
If anyone new thinks a good unregulated airgun in the 6-45ft/lb area can't maintain a 20-40fps shot count of at least 20-60 shots, you're just wrong.
For hunting and low shots, any PCP is fine.
For high density pesting, or precision shooting at 25-??? yards? A regulated rifle shines. As long as it isn't limiting the required power for heavier pellets or slugs that may require more air usage.
I myself have all types. Non regulated, internally regulated, tethered step down in-line reg, springers/gas rams, etc.
A regulator shines for some, is a hindrance & PITA for others. I personally like the step down in-line reg for testing of all PCP's. As it allows adjustments easily and faster, with no worries of a leak.