I have noticed that not too many pop rock/punk bands get too creative with their bass lines. Even being in mostly rock bands I have noticed I will try to write a different bass line and be told following the guitar would work better. Why is this? Is it too difficult to compete with two other guitars? Leaving you little room to explore before it gets too chaotic. Obviously there are some legendary rock bassist and even bands like modest mouse seem to have bass lines that don't follow the guitar but I notice a lot of the pop punk bands seem to just mimic the guitar.