I just install Aviate or some other thing on top of TouchWiz on my Galaxy 5. Who cares what the default UI is like, you can replace it is enough on Android. I think you can get any kind of Android UI you like, you're not stuck with what you get from the manufacturer.
Not all of it. In one of the recent HTC updates they pushed some incredinly inane "features", for instance a "volume warning" that forces you to click ok to move the volume past about the halfway point - even if it's the BLUETOOTH volume.
