Great review. You captured many of the same issues that I found with the game.
It's unfortunate that you poor Australians didn't get a chance to try Rock Band. I found it to be the better of the two by far. Once you get used to the quality interfaces that Rock Band has, it's hard to look past the clunky changes that Guitar Hero made while copying it.
To be fair, Rock Band had just as many if not more problems with the peripherals, but Guitar Hero was being held to a higher standard since Red Octane (the original peripheral makers) were making them. While they were better than the original Rock Band, they still had many issues, mainly to do with the drum pads.
It's unfortunate that the music studio is being overlooked by so many people. I'm glad that Guitar Hero was willing to go out on a limb to try it, but it seems their market just isn't interested, which isn't surprising when you consider that the Guitar Hero franchise was never made to appeal to the musically creative, but rather to the people who enjoy music and yet couldn't play it themselves. Hopefully some people will make use of it, but I've yet to see a reviewer who tried it.
It's also sad that there are so few singers out there. I just happen to be lucky in that singing is one of the few talents I have, so it's not painful (for me or everyone else) to be the singer, but it sure is noticable when somebody else wants to try it out. It makes me think we need fewer kids dreaming of being guitar players and more of them dreaming to be singers. Besides, the chicks are almost always hot for the lead singer of the band (even if you look like Steven Tyler).