I agree, the song listing is seriously crappy compared to the first, but I suppose that was to be expected really. I've heard lots of people complaining about the singer for the Nirvana song, but tbh, I find the singer who did the RATM song WAY worse. He's horrible.

I completed Hard Mode in one sitting, so I can't say I noticed anything impossible, although it was definitely harder than the first. The worst thing was just lack of enjoyable songs, though.