I'll say a couple things here... First off I'm a big fan of Oregon cam grinding (in Vancouver Washington) there's an old man named Ken that owns the place and you can ask for specifically. No waiting in line no waiting for some techline kid to call you back and no hype..
With that said you may want to put your questions out on the Race part of the Forum and start a thread there... keep in mind you're going to get a wide variety of opinions... What I usually do is collect all these opinions and draw my own conclusion... always remembering this is the internet and there are people who are able to write and say things that self-perpetuate themselves into being the correct answer when it's just ego...
I believe a lot of advancing or over advancing your cam will be experimental to your specs... I believe there'll be a baseline to work by in the cam grinders should give you that. Also remember Hughes engines does not grind cams...
keep in mind you're talking to somebody who has been told they have the slowest Stroker motor on the entire forum...lol..