Neopixels and button control

This I don't get. The advantage of neopixels is that you can have strips containing many LEDs without the problem of running out of PWM output pins. With ordinary/dumb RGB LEDs, 3x PWM pins are needed per led, so an Uno can only control 2 LEDs, for example.

But you only plan to use a single led, so why use neopixels? Am I missing something?