Thanks for the story sir. I would suggest over my very recent experience with this similar setup and matching expertise: #Pro I would suggest NPM as a viable proxy to menage over view of multiple subdomains over more modern solution unless load balancing is needed to scale up. NPM-gui is a sane choise to go for.

#Cons I would suggest buying a domain and transferring it to Cloudflare to set the dns to subdomains (and generate multiple ssl certs with DNS challenge plug-in using NPM[-gui])