Technically, every song can be beaten on Expert while the handful of double-bass songs on this game must be beaten on Expert+. Compared to GH:Metallica, this game's Expert+ selection is rather weak. For the majority of them, you can probably pass them with one pedal.
Up until Painkiller, the Expert+ songs are only labeled as such because of parts here and there with short bursts of double-bass. Painkiller and the last group of Van Halen songs are the only ones that should present any problems. When in doubt, focus on hitting the pads right and just go to town on the bass pedals. I did that in several spots on Painkiller and got through it easily. However, some songs like Hot for Teacher and I'm the One are going to outright take practice when it comes to the bass. The rhythms aren't tough at all, but you're probably not going to get away with the strategy I just mentioned.
You can always get a friend to hit the bass pedals for you while you drum away, too ;).