Just one thing regarding dashing USmashes. If you do it correctly, it should land properly on opponents, but from what I'm finding, there is a bit of start up lag in front of the person, meaning that they can grab you before your attack touches them. Though Usmash kills opponents, I prefer the strategy where your opponent has to do all the thinking in order to win:
Throw your opponent off the stage and then whip out your chain and start flailing it around the edge. Most of the time, you flail your opponent so that they fall straight down, and once they use their upB, they'll be hit by the chains continuously until they die. If they grab the ledge, then just continue to flail as if they are trying to strike you, your chain will get first priority to hit your opponent and they fall before their attack animation starts.