Simple answers, actually (which hopefully don't come as a disappointment)

1.) Nope, no such app exists as of now. This isn't so much related to software because the functionality has to be supported by the actual Bluetooth hardware in it.

2.) It's a recognized problem. There is NO queue list. It assumes that you're aware of the apps which have been queued, then any amendments to the queue list are to be made by browsing the individual apps. Troublesome, yes.

3.) Unlike the previous iPods including the iPod Touch, the iPhone does not support 'drag n drop' music copying. They have to be synced in through iTunes. There ARE ways around it but iTunes is still pretty much the most elegant solution.