Well researched and presented!
"I plan to curate my artists, record exclusive videos from my London studio, and share them here. I'll split revenue with the artist, and use a % of it to advertise videos on YouTube."
I think you're in an ideal position to push this forward, good luck.
One of the benefits of Steemit is that 'sidechains' or apps can be built alongside it, you'll be able to transfer over your steem dollars from one 'chain' to the other. With the mass market appeal of a social network combined with all the issues of current systems that you explained above we could really see some revolutionary progress here.