drive4fun- Welcome to Autopia!
IMO you won't go wrong with any of the pad choices, they're all good and the PC isn't as pad-sensitive as the rotary can be. I'm not familiar with the Edge choices, but I have noticed that there are a *lot* of barely-different pads these days. You really only need light cutting pads, polishing pads, and finishing pads (IMO).
I do think the 4" pads are necessary for real correction but I don't know how often you'll need to do that. Handy to have when you *do* need 'em though.
I'd also check out
TOL and
CMA , as well as the sponsors here
To get anything special out of the PC (as opposed to what you can already do, if not as easily, now by hand), you'll need an abrasive polish. There are a zillion choices but I'd sure look into Optimum and the offerings from 1Z (maybe
PAKSHAK has them, I forget). And I dunno if I'd be so inclined to switch from a wax-based approach to
Klasse. I use the Klasse twins on one of our vehicles, but I honestly don't think it's the right solution for everybody. I probably recommend Collinite waxes more than anything else. Optimum or 1z polish, topped with a good wax, will look great, be forgiving of any remaining flaws (especially the 1Z), and will last a long, long time. Sorta similar to what you're doing now too, which can be a good way to progress to a more serious level of detailing.