I am not good at names but
Whonix-Host is not good.
All Whonix-Hosts are Whonix’s host, but not the opposite.
Many other OSes can be a Whonix’s host.
When you are reading for a long time, it is easy to not get the point that Whonix-Host is meant to be an OS developed to be a Whonix’s host, not any other disribution with different purposes.
When talking about Whonix OSes, there are two deployed as of now, Gateway and Workstation. Gateway could be named proxy, but Gateway is a much better name for people to imagine what it does, it is the gate to the internet. Workstation could be named userspace, but it actually conveys the meaning of the station the user should work. I think “Host” is ambiguous and should be changed to another word.
Searching for synonyms of host does not lead to relevant alternatives, but searching synonyms for manager and control does.
Maybe these names are not good, but Whonix-Host is easy to be confused.