No, you don't. Source: I've had an account for years and am not paying anything.
> it's a PIA to setup and configure.
You add folders to a TV and Movies collection once. With Kodi, you're doing it N times, where N is the number of Kodi installs in your house.
> Once configured, don't plan on using the computer you setup the Media server on as it is always busy/ bogged down scanning files and transcoding video
As others have stated, this is not the case. My Plex server is an old Core2Duo MacBook Pro that also runs virtual machines.