I really like your luigi. You're probably better than I am, but I think I still have a couple things to add.
Stop rolling behind people, I didn't see it do good things for once in that video. And the best result you got out of it was meta rolling away from you.
I personally think Dair is a better option in your shorthops (where you throw fairs). It comes out on the same frame (I think) and it's hitbox extends lower. It does 1 more damage, and it's knockback is better (lower at lower% and higher at higher ones).
You ought to learn to throw a fireball into your game. Possibly your shorthop aerial to a landing fireball. A shorthopped fireball into your tornados. I don't have any real suggestions beyond that, but learning to throw them in now and again varies your playstyle (in your oppoent's mind) without you really having to do much. Lanuigis combo video is a good place to look.
One last thing, nair would have killed that meta alot sooner. And you telegraphed all those bairs.
Great stuff dude. You're really quick. Your fundamentals are solid. Do us all proud.