As has been discussed in the other 57 threads about neopixels, 3.3v processors (like the 3.3v Trinket, Gemma, and Teensy) may need special handling. Some of the newer neopixels are more strict about wanting 5v (some of the early versions could run on directly attached to a lipo, and using 3.3v signalling). For example, I have a 24 led ring that will not work unless you power it with 5v, but with that ring, you can signal with a 3.3v processor (my 16/12 led rings, and 1 led stick work fine powered with either a Gemma or Trinket). Others have what they call a grumpy strip, that needs 5v, and the signaling also has to be 5v. Many of the voltage converters (for things like i2c) are not fast enough for doing neopixels. I would expect over time, it would be more likely new strips/rings that you get might be grumpy versions.
So, for something using neopixels, it might be simpler to go with 5v processors and batteries (unless you want more of a challenge). Unfortunately there are some sensors that only run at 3.3v, so you might need to do voltage conversion, but a lot of things aren't as timing sensitive as neopixels.
Finally, things that use interrupts like servos, might be problematical with a lot of neopixels.
I'm not trying to discourage you from playing with blinky lights, just trying to avoid some head banging that is currently being discussed.