Like you I was so-so on the animations originally. They were OK, but nothing special. The more I play it the more I realize how clever they are. And really interactive.
For each song, the band is playing in a setting relevant to the song. They are always singing and playing in time to the music. But there's all sorts of other song related stuff going on.
For example in Back in the Saddle, the animation represent a country shooting gallery. Each shot on the PF you make shoots and smashes an object on the back wall - like a Sparky drawing and other stuff pinned on the walls. When you get Crank it Up in this song, the front of the shooting gallery gets lined with target ducks like in a shooting gallery. Each Crank it Up shot you get whilst in this mode shoots one of the ducks (yellow Aerosmith stand ups).
In Rats In the Cellar, at first theres only 2 rats walking around in the cellar. When you hit CIU, suddenly theyve had heaps of baby rats that are running all around the floor.
In Dude Looks Like a Lady, the back wall is lined with black silhouettes of dancing women. Each shot you hit, one of the women is revealed to be a man and now its a man dancing in that spot on the back wall. (Wonder if these guys are Stern staff??)
Pretty sure all the other songs have something similar.
Also on the left border of the LCD there is a Joker picture with a number in front of it. This is an Extra Ball mystery shot counter. One of the extra balls is awarded (lit) for "mystery" shots - they are just one of the main shots that are not lit for a mode, randomly selected. When you get to 4 or 5 EB is lit. You know youve hit one when a seemingly random coloured Joker pops in from the sides or top/bottom of the screen.
You can tell a lot of time has been spent coding this game, and its a great showcase of Spike 2. Lets hope all future games get the same thoughtful use of the LCD. Will all depend if they are give enough time to code it.