What would be handy with dozens of VPSs would be to control them as one for numerous things. Do you know of anything which does that from
Windows?
This is "server automation". Ansible, Chef and Puppet are popular solutions. Ansible seems to be popular for Tor relays, with several existing playbooks available (search for "tor ansible"). I'm really not much of a Windows guy so I'm not sure about the extent of Windows support.