I don't recall if I ever was able to enable a logging session (If I did I don't recall how I enabled logging the connection attempt). If Remote Login is enabled, then you may first need to establish an SSH tunnel before being able to connect using VNC. When using the command line I am prompted for the Mac's VNC password before it launches a window for the remote GUI session.
I have also enabled 'Observe' & 'Control' found on the 'Options' button for the authorized user. They're generally built for remote admin. IME most remote access solutions will be laggy when doing intensive graphics work. On the Mac I have enabled a VNC password (click on 'Computer Settings' button under Remote Management). i mean when people connect to there macs using vnc viewer to there macs its just laggy, especially when there doing any graphics work on it ie adobe cc photoshop etc etc.
On Linux I use the following command to connect to a Mac using VNC (xtightvncviewer is being used - I believe you can just use the tightvncviewer command as well): vncviewer Plus different versions of macOS seem to behave differently. I don't have these issues when connecting to a Linux remote system. Even when I connected to the remote Mac the graphics in the session were very slow to load and both computers are on the same LAN. When I was having trouble I was able to enter my VNC password, but a VNC window never opened. After disconnecting from the VNC session I was unable to access the remote Mac via VNC for a while. I had to try multiple times before I was able to connect. I actually was having trouble connecting to a Mac using VNC myself.
