Definitely tech skill, not talking about doing wavedashes and wavelands everywhere, also work on being able to move ...IMMEDIATELY... as soon as you can out of attacks, aerials, grabbing the edge, whatever. You really gotta work on crunching time as ganon.
One extremely extremely important thing you can do that's probably easier to train alone is ledge teching, do the whole proximity mine on the edge in training mode and just keep practicing. Beyond just getting the tech, i'd practice doing the tech wall jump to an instant up-b (into the stage) to practice being able to hit people with it who are too close to the edge and trying to edge guard you. It's a really handy skill.