Installing on a Mac is pretty straightforward, there's not a lot to it to be honest. Though I do see more people having issues with some plugins when running on macOS or even windows than when using a Pi, which seem to be very robust. And as you mentioned you’re then running your Mac 24/7.
If you decide to go the Pi route then there’s a great guide
here I’d say read through it all first before you do anything. Just to get familiar with it. Don’t worry it’s nowhere near as scary as it looks
😀
There’s a section near the bottom regarding auto start on boot, I’d probably pm you something on that bit because it can be nightmarish if you’re doing it for the first time depending on the method you choose (I always favour straightforward and simple, suits my brain
😀 ).
You can run Homebridge on almost any Pi, I’d say get a 2B onwards. The bigger ones such as the Pi 3B have the advantage of an Ethernet port and a good bit more processing oomph, which can make a surprising difference even for something as simple as Homebridge.
But I’ve setup Pi Zero’s with it too and there’s been no problem. If anything I’ve seen occasional slight delays with some requests on the Zero, but we’re only talking in the second range. The newer Pi Zero W is best if you’re going for one of those due to it having built-in WiFi and Bluetooth.
And you’re more than welcome to pm me if you’re not sure of anything, I’ve setup a few on Pi’s now so I’m a bit more familiar with that and I’m sure others would oblige.