I can touch on some of that. BD really is a function of your hardware when using hardware acceleration. There is little to no difference in quality between PDVD and TMT regardless of the version. However, if you use software decoding and apply filtering or use something like madVR, then yes, you can affect quality and in theory improve upon it. TMT5 gives me absolutely breathtaking quality in DVD and BD, so, I have zero complaints there.
As for the ReClock trick, I don't know if that still works. I never had a system where I could try it. ReClock itself still works and we'll hopefully get an updated version from James that installs it correctly for TMT5.