I sketch everything. Screens, call flows, processes, hierarchies, etc. It drives me crazy to be in a meeting and people are throwing ideas around and arguing and stating their points and not seeing the connections between things, and no one is trying to capture anything on a whiteboard. It so much easier to see the relationships between things when you write them on a board.
I was so delighted to find the book Business Model Generation by Osterwalder and Pigneur. Here is a book that elevates the importance of sketching and group facilitation and design thinking to the highest importance in creating new business models. It has been out of print for a while but it's finally back. Highly recommended.