There’s so much and I don’t think there is one area. Gaps are everywhere. The more you learn, the more you know you don’t know. The Middle East, for example, is not well studied. There are other gaps topically. Even in areas where lots of people have worked on, the work just brings more things for people to study.
I believe that we are all born artists. I know that you are a better artist when you are a scientist and that you are a better scientist when you are an artist. You can combine imagination with information.
One of the things art and humanities do at a big university is to make us all alertly observant. Art does have the power to make us newly aware of things that we thought we already knew.