Great OP, does a good job covering everything.
I only play PM and not Melee, but it's hella fun to watch and most technical stuff applies to both (but Melee is harder).
A huge regret of mine is dumping Smash entirely when Brawl came out. I discovered competitive Smash around 2005 or so, but I wasn't playing many console games at all at that time so I didn't really dabble in it. By 2007 I was back into consoles and instead of learning Melee I decided to wait for Brawl. Awful decision, because I didn't play Brawl for more than a few months before dropping it entirely. I still liked Melee, but it didn't seem like it was going to have a future so I didn't go back to it either. If only I'd known...
Also, yes, moonwalking might be unnecessary (doubly so in PM with RAR) but dammit I play Falcon and feel like I need to learn to do it!