Vegetables and side dishes - I would keep that chapter, for sure. Sometimes you have an easy way to prepare your protein (grill, for example), and can use the instant pot for a more elaborate side dish. So it makes perfect sense to me to have a dedicated chapter for side dishes.
Beans and grains, I would include that into the vegetables and side dishes. I just see them as one option for side dishes and don't eat enough beans/grains to want an entire chapter dedicated to them, but others may have a different opinion of course.
