I use the second git-project for some LED lights, when the user turns it on it fades softly to 100% (or any specified value).
Regarding WiFi performance:
I tried QLC+ using ArtNet as output (and a wired receiver) and 32 PAR cans, 1 Moving Light and some special effects (moonflower etc). QLC+ did fine BUT the amount of broadcast packets completely smashed the WiFi because broadcasts reduce the WiFi rate to 1 Mbit or so.
So in short: it MAY work, if you have only the spark core and maybe your controlling PC in your WiFi but if you play in a bigger WiFi network your WiFi clients may slow down depending on how often your controller sends ArtNet packets. QLC+ does it quite often - no matter if any channel values changed or not.
If your controller supports sending ArtNet packets to specific hosts it shouldn't be a problem at all.