esm, I personally favor berryz > c-ute for everything, but that's my biased opinion.
and yes i agree with you, the songs have been great.
jinqin, he doesn't arrange all the songs. He usually has a main idea for what he wants and then he has the crew pick up from there. I know this because my dad is a musician too and that's what he does for a living. Tsunku gives people the idea of what he wants, let's say certain chords and ideas for the song, and then other people arrange it and play the instruments and stuff for it.