Sure, like I said above, GOS doesn’t at all prevent you from rooting the device. They only discourage it from a security point of view. Regarding MicroG, I’ve never had need for it myself but I’ve read many other posts over the years from users who have installed it on GOS in lieu of Graphene’s own implementation.
I would argue that overall GrapheneOS provides more control over the OS than some other Android-based operating systems.
You can root GOS like any other Android-based OS. It’s just highly discouraged, completely unsupported and, in the opinion of the GOS devs, you will no longer be considered to be running GOS since you are compromising the core OS by doing so.
While Reolink hardware is perfect for Blue Iris and other self-hosted solutions, I try to warn everyone that Reolink’s own Android app now captures your device’s clipboard whenever accessed. The same may be true for their desktop or iOS apps, I don’t know.
I have several Reolink cameras and I’ve been happy with their overall image quality and capabilities, but I do not trust their software whatsoever and recommend keeping them isolated from the internet entirely.
I don’t use RCS myself, but there are recent posts on the GOS forums and it appears to be working fine once all of the prerequisites are installed.