So, with the air dodging thats a good example of making a commitment. If you go in for an attack that, if it gets airdodged and then they hit you back you should not have gone for that move. If someone is trying to get back to the stage, they are going to have to get closer eventually. Unless you have a direct follow up, its more beneficial to just be in their way, so they'll have to go past to get back especially against someone floatier. I find that going up close to them and not doing much tends to force a reaction, like an airdodge, that you can punish afterwards.
If you find they they will be in a position to come back afterwards, wait back on stage and try and read how they will get back from the ledge. There's a specific spot to stand in that will cover the most options. Its outside of the get-up attack range, so you can run in and grab if htey regular get up, and turn around if they roll.
You gotta be able to think like this, in ways that limit an opponent's options until its easy to make a hard read. When we played, all my moves connected because I was mostly cutting of ways for you to escape, and you were comitting to laggy options in neutral. You do have a strong command of peach's moves and know how to use them very well, but its still relatively easy to play against you because you make hard decisions easily. So instead try focusing on making yourself hard to play against. Try and stay mobile, using quick moves that keep you safe and block off incoming attacks, and when you do get an opening make the most of it by keeping the pressure on.
Amiibo's don't react to spacing and range in neutral the way most players would, so don't base your entire game off those matches. But it is still useful for figuring out different ways of approaching and being forced out of habits. When you play against it, pay attention to how you get hit the first time. Like what did you do, that allowed yourself to get hit. Then you can apply that, because now you know a certain way to counter the approach you did. Then when other players do that to you, you know what to do. Try different things, make the most of the openings that you do get, don't get hit.