I am just a regular user with good system understanding but I am not a software person by any means. Therefore, take the following with that in mind.
I feel myself trapped between HASS recommanded install for a Raspberry Pi, and MSR recommanded install. They are not compatible...
HASS recommanded install is using the Home Assistant Operating System, a controlled environment where the user do not have control over the OS. The good point, it is simple, very stable and protected against noice user like me. On the other hand it make it difficult to do anything else like installing MSR. Trough the Portainer Add-On, I manage to install the MSR container and to configure it to see my Vera and HASS devices. The problem is that the configuration is within the container and when we upgrade or remove the container, the configuration is lost.
The fact that the standard MSR container is running just fine (beside the config) means that the configuration is compatible with HASS OS. I understand your approach (not being system dependent like Reactor was with Vera) by providing either a generic container or tar ball but it implies having a device on which we have the control over the OS. Your actual container for Pi is so close from being an official add-on I wonder if it would not worth the effort. I even see a benefit for you when trouble shooting. The Hass OS environment being almost lock, it can become somewhat of a referece when chasing down an issue with MSR. How many problem are due to the user changing something it is not supposed to. The other thing is, how many users out there, like me, are using the Pi image or the Home Assistant BLUE platform.
I have been using (and contributed) Reactor and Virtual switches with my Vera and I definitely want to go that route with MSR and HASS. I will re-install HASS with an alternate method if I have to, but it is not my first choice if I can avoid it. Again, being just a regular user, simplicity is paramount and the HASS image was pretty good. If MSR could be an add-on, it would be fantastic.
For your consideration.