Since Falco's predominant movement (in neutral) weakness is his x-axis mobility (compared to others), and since wavelands and wavedashes greatly make up for that deficiency waveland movement tech is likely better than NIL tech for falco specifically, were the two to be pitted against one another as exclusive options.
However, stuff like invincible ledgehop->NIL->(grab/shine/dsmash/fall-through dair/bair/etc) as an optimized option would be insanely hype, so using no-impact landings to gain frame advantages and fall-through options vs regular landings and wavelands, on top of being able to use wavelands as a movement option, I think would be terrifying if added to your option spread.
Also, I might be wrong, but falco's ECB might be in a perfect position to perfect-waveland (full X-direction) on plat if you can NIL like that, which would also be a really good movement option.