I'd like to see a single global licensing body with a harmonised and simplified model covering every component; record labels, publishers, performers, writers, download rights, artwork, etc. There could be ways for them to support small broadcasters - by providing access to a large catalogue of digital music, waiving fees in exchange for delivering ads, etc. From this we'd see some really innovative services bubbling up to the top.
However, I still stand behind what I said - if you want to turn a service like mixturtle into a viable business then you have to play their game, which is very difficult. I know it makes me unpopular, but it's just a reality we have to live with (for now).
I had discussions with PPL and MCPS-PRS here in the UK a long time ago - their model is pretty complex - and if I wanted to have users in other countries then I'd need to get licensed with their representative bodies too. Not to mention the issue of download rights and artwork - all that has to be negotiated directly with the copyright holders. I'd wanted to build an ad-based model, but in the end I couldn't see any alternative to subscriptions, so I gave up - I couldn't afford the £10,000 advance fee.