Personally, I prefer functionality over looks. That is why I continue to use Neutron music player despite how horrifying it's user interface is. But that isn't most people's cup of tea. If you just want to listen to music without the hassle of fiddling around with half a dozen sliders and knobs, players like Apollo, Google play music and the like will suffice.

Gramophone is a music layer targeted at this user base. In terms of functionality it brings nothing new to the table. Where it stands out is in it's design.  It does a great job implementing material design, and the interface is fresh and intuitive.

I realize that I'm making it sound like I'm recommending it just for it's aesthetics, but it has all the functionality most need, and then some.
It has Last.fm integration and even has a built in ID3 tag editor to edit details of tracks. It also works with AudioFX on CyanogenMod. Gramophone has a homescreen widget, but I had trouble getting it to work for me.
Gramophone is free, but is in closed beta right now. If you want in on the action, you have to join Gramophone's G+ community to download the beta.