Arthur, you need to mixup delaying your aerials.
Your approach is Laser into SHFFL Nair, so if they keep shielding after the laser, you should delay the nair so it hits their shield right before you land. Then you cannot be punished out of shield. Trust me, with Sheik I could Nair out of shield your falco approach for days.
The reason you want to Nair quickly like that is for when your opponent starts attacking you between your laser and your late nair. That's why you need to change it up. I think a big problem is that you almost always approach with laser to Nair, but just delaying your nair sometimes at least may throw off your opponents enough.
If you always do your Nairs and lasers at the same Rythm, people catch on fast.