@eselarm:
First off, thanks for your extensive answer and the effort you've put to read and answer to my question. I'm by far not such an expert like you yet, but to start with, I can tell you the following:
I had two Le Potato SBC laying around doing nothing and I wanted to give them some work to do. I was already looking for a while to start with HA (I have currently an own written home automation system that works together with openHAB through MQTT).
The Le Potato has (at least mine) 2GB of RAM on board, twice as much as all of my Raspberry Pi's I currently have or in use, or laying around doing nothing. So I think that should be sufficient to do what I want to do with HA. Le Potato is not a racing car, but I don't think this is necessary for me. Unless you have so many add-ons like you have. That's another story.
I want to use Zigbee as a protocol for my sensors. I bought recently a whole bunch of them: presence detection, door and room sensors, temperature sensors. All of them from Aqara.
I also bought a Sonoff Zigbee 3.0 USB Dongle P (later on, I read that I should have taken the E version but yeah, that's the "learning price" you pay if you step into an unknown world...)
Next to that, I also bought presence detectors from another brand (HOBEIAN, model ZB-PL/ZB-p: this seems to be a Tuya clone), just to see how HA can cope with all those different brands.
Finally, I also bought 4x 2PM GEN4 Shelly boxes to contol roller shutters later on. The nice thing about those is that they "understand" quite a few protocols, among others, Zigbee
I also want to be able to "listen" to what the Zigbee components are sending to HA. Therefore, I want to use Zigbee2MQTT in HA instead of Zigbee Home Assistant itself.
It's for Zigbee2MQTT that I really wanted a HA version with supervisor capabilities to be able to add Zigbee2MQTT through the Add-ons feature. Alas... that's not seem to work...
So, my Le Potato should only be able to run HA in combination with MQTT and Zigbee2MQTT. The specs of Le Potato should be sufficient to cope with this I guess (I hope). And if the future demands me to add more features, well, then we'll see. But my first goal is to learn HA and its surroundings. And since I anyhow had those SBCs doing nothing....
So, since the "official" Armbian Home Assistant image didn't have the Add-ons feature, I took a brave and daring move: I went the HA docker way...
Therefore, I took another SD card and flashed Armbian 26.2.1 Minimal to it. Just to have a very bare bone Linux distro (I have to admit that I do know something about Linux, I'm just not a HA expert yet...).
After installing the distro on the SD card and doing the necessary "Armbian onboarding" stuff (create root password, create new user, and so on), I first installed Docker. Again: I have no experience yet with Docker, so again another big gamble. But I like challenges, so I don't mind.
After installing Docker, I installed the HA docker image. I then opened the HA web UI and could also start creating a "first user" (which is apparently given administrator rights). But of course, again not the Add-ons feature in the Service section. But this time I could understand; this is normal since I didn't use the real, official HA repo.
I could install ZHA, however, which I did. Just to see if my Sonoff dongle was detected and used by HA. After installing ZHA, I activated some of my devices and yes, they were detected!
But that only proved my Zigbee dongle was working fine. Nothing more, nothing less. Still, very important!
Then I installed Zigbee2MQTT "the Docker way". This was absolutely not a walk in the park, but in the end I got it up and running. My devices are getting detected, I know now how to change topics. I can receive MQTT topics on my MQTT broker running on another Raspberry Pi, I can filter the MQTT JSON objects so that I only receive what I would like to receive (by default, the JSON object exposes all entities of a device, but I'm not interested in all of them), I can convert the standard MQTT topic "prefix" used by Zigbee2MQTT on the fly and so on.
Overall, I'm very satisfied with what I currently have and I will continue to follow that road. Maybe until Armbian has a fully supported HA image for Le Potato that contains the Add-ons section.
Maybe I will switch to a more powerfull server too in the future. I read on the inet that a lot of people are switching from a RPi4 to a so-called Intel NUC server (whatever that is, no experience with it, no idea about its specs) for performance reasons and they're very satisfied. Maybe I'll do that too in the future, only God knows...
We'll see, but still lots to learn about HA and its overall environment for the moment.
Thanks again!
Best,
--Geert