For me, the first goal is to simply understand the setup.
I now have been able to create a setup with two frontend jvb-instances and one backend. In the end, the architecture setup of a jitsi-server is quite nicely explained, and -by delving a little bit into the startup scripts of the docker-based jitsi setup, you do get some idea of how things fit together.
From a practicle point of view, I think I'll go for the basic setup (1 backend, 2 frontends) natively on two servers, and -if the backend server would go down- just have a dockerised backup-setup ready to go if it would be needed.