I've used mic cables for 1000+ shows over 20+ years with no issues. I guess most of my runs have been at most 100-200 feet if distance is the issue. Wireless/wifi controllers are the only things I've had consistent problems with.
Can affirm Art-net is supereasy to implement indeed. One thing you shouldn't skimp on is the DMX controller. I've used DMX to USB controllers in the past, but those have lots of driver issues. The better ones operate over Ethernet and you can just use UDP. I've been using a Showtec box, but i'm sure there are other alternatives as well.
Yup, they're definitely cousins. The only reason I didn't mention OSC is because you're not going to have the same ecosystem of existing open-source and commercial lighting control software available. OSC is fabulous for controlling all sorts of things and nails that COTS software compatibility layer for lots of other live production scripting stuff. (e.g. if you implement OSC on an ESP32 you can control what it's doing from an existing iPad app)