I pretty much agree with your observations but I'll add that saddle angle depends a lot on the saddle shape (and your shape of course) - I don't have any saddles that tilt down but all of my more modern saddles are level while my Brooks professional and Cinelli Unicanitor tilt back slightly and my Brooks Champion Flyer tilts back quite a bit. The one thing my new saddles have in common and that is different from my older (or older design) saddles is that they are completely flat. Setting the saddle level works perfectly - you don't slide forward and the nose doesn't press into your tender spots. The older ones always seem to have a dip in the middle that forces you to angle them up. I had to tighten and lace the Champion Flyer to make it rideable for that reason.