For the fist tests, I have installed netmaker on one server and an ingress/egress gateway on the second. The reason is the limited IPv6 support inside docker. Is it secure to install netclient on the docker host to provide ingress and egress functionality and leave netmaker-1 docker for pure management? - If yes, is that something the project will keep supporting?

yes, in fact the netmaker-1 node inside of docker is likely to be deprecated in the future

Thanks. Seems to be a clean solution that way.