I still don't think you've nailed it.
'nothing to download'? I don't ever have to download to watch a video on youtube. Grooveshark let's me listen without downloading or signing up.
No search is great if the user can find what they're looking for, but I don't feel like you've nailed that yet.
I'll have to disagree with you on design. Core functionality isn't functional if people don't use it. Design is not decoration. Think UX not UI. It is hugely important to the success of your start-up. I know. I created a site that people raved about the design and was growing nicely. I redesigned it to add some 'functionality' I thought people would appreciate, and people hated the new design and that growth came to a halt.
Good luck with the UX, my suggestion is still to stick to something people are familiar with, don't go re-inventing the wheel.