What's the top music player?
Title: Simple Music Store Or just use a clear name like "iTunes" or "Xbox Music" style.
Platform?
You're currently using Google Play Music, offline playback on YouTube, and it's quite affordable.
This is exactly what you're looking for.
PC...
It's great! You can connect to your server using VLC as well.
I primarily rely on Amazon Music, utilizing their AutoRip feature for my CDs. I also own a CD player and a record player.
Spotify has a great look and is very easy to navigate.
MusicBee is quite pleasant.
Foobar2000 is the top choice for me.