So I have a VPN set up through my Unifi UDM Pro. Teleport is crazily easily through their WiFiMan app but L2TP or OpenVPN are also fairly straightforward. Once you are into your home network you can get to the “local” administration page of your ROCK and hit the “restart” button of either RoonOS or the Roon Server software. If you remote power cycle the machine it always has some risk that the NUC will power off and not go through a full restart, but that’s an intel hardware issue not Roon. And if your machine is in a really bad state you obviously won’t be able to get to the admin page.
Of course this only works if you have a VPN on your home network and use ROCK, but these were (admittedly very minor) considerations among the many why I use ROCK.