but a coworker was using a Pi-2 as a home media server without issue in some situations - basically he did the math on the bitrates per second and determined that the disk/wifi I/O (on the shared USB bus) was fast enough for his use case (IIRC streaming to main TV, possibly 1-2 more devices)
I do know he was looking at upgrading to another mini-arm board with a dedicated PCI Nic or separate SATA due to the bus contention on the USB limiting data/network I/O because he wanted to serve more clients (family of 5 and associated devices)
so I guess the short answer is 'maybe, depending on use case'..
Once you have the files on the disk attached to the board just set up a NFS and/or SMB server on it and let the clients players mount it as a network drive and suck the data. This way you can for example have all home TV sets playing each one a different movie at the same time.
Absolutely. It's easy to install, works great, the only problem you need to solve is DNS. Either you need to use a service to point the domain to your dynamic IP or rent a static IP for your home address, which could pot expose your home network to attacks.
>things like video streaming from this would be slow
Depends on your uplink. Probably. If your home internet is fast you can stream for yourself or even a couple of people, but you can't really run a video streaming operation. It's easy math, just watch your bandwidth while your stream a video. On private customer plans, uplinks are usually artificially made a fraction of the bandwidth of downlinks by ISPs because they want businesses to be unable to run on them and buy the more expensive options instead