Maybe take a look at the Amazon Fire 7 Tablet. Currently on sale for $35.00 . You can load it with your own digital music files via computer file manager (PC) and Android Manager (Mac). You can use Amazon apps to download and automatically organize Podcasts and Audio Books. During a long car ride, you can connect it to WiFi via a cell phone HotSpot.
And, you could insert a 16 gb or 32 gb or 64 gb micro SD card for even more storage of music (& some videos).
The Amazon App Store has some useful apps for playing your music files via Folder Play.mode. Then you do not need to worry about curating ID3 tags. AND, you can use Spotify on this tablet.
