Fit the display to the viewer
Use Fit to This Device and the host creates a virtual display with the viewer's shape and pixel dimensions. The stream fills the available screen instead of inheriting a low-resolution fallback from a disconnected monitor.
Stay reachable while sharing
The Host's Keep Mac awake while sharing switch holds an idle-system-sleep assertion only while sharing is enabled. The physical display can still sleep while nobody is connected; an authenticated session keeps display capture awake while it is in use.
Return automatically after login
Enable Start at Login so MacReacher Host returns when the macOS user reaches the desktop. macOS does not allow a screen-capturing user app to run before login. FileVault protects the disk but also prevents automatic login after an ordinary power loss, so plan a separate recovery path for a critical unattended Mac.
Remote restart, explicitly enabled
The host owner can separately allow an authenticated client to request a restart. MacReacher uses macOS AuthRestart for a FileVault-protected one-time reboot when available, but it cannot bypass the normal macOS login boundary.
Connect without opening a public port
Use Bonjour discovery on the same network. Away from home, add the Mac's Tailscale or other private-VPN route. Public port forwarding is not the supported deployment.