Why should G&W rise? If anything, the fact that we know how to fight him better, as well as how far we've brought SDI/DI, should at LEAST make him stay where he is, if not make way for somebody else. His smashes are all good, but you can evade them all on reaction alone if you keep an eye out when you're at danger %s. If anything, they're only usable when you want to punish someone you baited/trapped when they had no other choice but get hit.
I don't know what's been going on with Olimar and Pikachu these last few months, but I'm willing to bet my left sock that nothing special has happened with either of them. DDD, should stay in bottom of S/top of A, since he is a fundamentally great stand-alone character with no horrible matchups aside from ICs that does very good across the whole board. Diddy should stay where he is and Falco should stay 4th for the amount of good options that they give the player in every situation (pretty much just a small overview of their traits). Rob, I don't know what to think of him; I've always thought ROB isn't A-tier material, he is too easy to juggle around, and some characters have very nasty things they can do to him. Not to mention that his aerial kill moves are like WOW telegraphed, making his fsmash and grab his best bets at killing opponents (besides gimping)... I really think he got that high due to his huge recovery distance, but like I've stated twice already, these are just my opinions.
I also think the IC's grab shenanigans were overhyped. They're good as well, do good against the whole cast, and have 0>deaths on everyone, but you gotta admit from what we've seen... Getting that game-breaking grab when you truly need it is a pain, and the way you can be separated from Nana so easily and have her die due to a juggle done against her and her lack of evasive maneuvers thus leaving Popo alone in a disadvantaged situation, is too tough for the IC mainer, as well as something we see in every match.