I'm sure you understand by now that true gamers wont accept any input devices besides buttons and keyboard mouse. So I'm sure its good, but you know
"I have to use the touchscreen FUCK THIS MY DS"
The touch screen controls worked fine for me, better than expected. It just made it more confusing that I didn't think it was nearly as good as the GBA game.
Band Brothers, Wii Music, Ouendan, and Rhythm Tengoku are all more mechanically interesting (Band Brothers is a close comparison). The only feature of guitar hero/rock band that would separate it from the countless fake instrument games before it is managing the star power and deciding when to activate it. Which unfortuneatly doesn't affect anything other than points. So dull. -_-
You make it seem like the fake instruments still amount to just pressing a button on a large plastic object, but they actually mimic the real instruments in both feel and play style for the most part. Like, It's one thing to press a button that's coming down the screen, it's another to strum to time the note and learn pull on/off movies. The drums are also not just pressing a different button for the base peddle, you need to use hands and feet together to properly play. I have played all those games you listed and Guitar Freaks, Hero, Rock Band are much more than Band Brothers and Ouendan. The other two can't really be compared, especially Wii Music.