I would use it to make music recordings and to listen to Dad's old collection of RTR tapes. When I was a kid, I had a lot of fun making recordings from his "sound effects" tapes. I think my 13 yr old daughter would enjoy it too, as she thinks all this old gear is cool.
I'd also see if I could find additional old music reels - there's about a dozen for sale at a local record store that range from 10.00 - 35.00 ea.
Also IMO it's would be nice to have another piece of kit not MIC!