^^^Hence why i think marth is better.
I think wario still is third best simply because he so evasive its not funny. You can rarely hit him. And his moves have high priority and do decent damage, and because of his aerial movement he use them all very safely.
Diddy i think is worse then wario only because you can counter diddy in two major ways, counterpick good stages that will neutralize his naners. And some characters i believe outright beat diddy, when they get control of his bananas, ex. Ness , my main, can do crazy things with bananas, and when i'm in control of them diddy suffers from not only him not having them , but that it enhances my characters game like it does to diddy. And diddy does have average way of killing, as in not good or great KO power.
IC- i don't think i need to explain, they have clearly risen.
Falco i believe is below IC is because he can get destroyed offstage, by really anyone. And any character that can avoid lasers like kirby, or can out camp him, virtual stops his main advantage over characters. He is still a ridiculous character though , his camping does shut down alot of people. And he shouldn't be taken lightly. The gap between him and IC is minimal IMO, i'd say they are the same spot, like olimar and ZSS were on the 2nd tier list.
Marth is better then D3, mainly for the reasons Vex said, and because of that Marth benefits from it.
Thats the brief explanations, i have for what i put.
EDIT and i believe the cut of is still
S-tier
MK
Snake
Wario
Diddy
IC
Falco
A tier
Marth
DDD