I haven't enjoyed possessing music since my phone replaced my ipod. Maybe I didn't try hard enough, but the seamless* updating of my library and playlists on iTunes and iPod was great. The poor format of the music I did pirate off limewire wasn't as big a deal - partly from the smooth UI of iTunes, partly due to lower music acquisition. I say seamless* because it was problematic when my iPods got full, having to cull the library, but I do beleive it was simple enough to drag selections and individual playlists.
But now what? I don't have a program to load my pc and phone, I never liked what I found for music management on windows, as you said formatting isn't consistent on torrents, and my phones fill with pictures faster than music. So, in comes Spotify. Anything I want on a whim, shared playlists, I do enjoy not storing music myself, the social aspect of public playlists, and an option to store things offline. It's similar reasons Netflix curtailed my pirating. But, as a warning to Spotify, if music streaming services break up content like Netflix, I won't wait to cancel my subscription. That'll be my push to start whatever suggestions I imagine I'll get here in the replies