I'm just afraid all this virtualization you intend to do will mean less enjoying stuff and more configuring it.
Amen. Unless you're just REALLY into setup and config and maintenance of multiple units, a bunch of infrastructure will get old FAST.
Build a box, slap a PC with a 2TB drive in it and your mame cab is done.
If you want to serve up media, get another box with 2 big drives, mirror them, and load it up with your media. Backup your GAMES folder from the Mame box to your media box, and then backup all your media to the cloud.
If you really want simple, build a Jukebox separately, and just put your media there, don't worry about streaming/virtualization/etc/etc at all.
Now, that's assuming you're not shooting for am MCSE or some other certification. Hell, I had win server with MSSQL and Exchange running for years while I was learning how to admin that stuff. But, that got old, and I moved to GMail and SQLExpress. Now, my server is just one big mirrored network drive that backs itself up to the cloud. Really simple.