I don’t consider myself an ideation expert, but in my role as a sketch artist I’ve been involved in many ideation exercises. Not actually ideating mind you, but the visual facilitation and capture of ideation. You could just say I draw people’s ideas.
We use visual metaphors a lot. They're a powerful way to make a point quickly and many easily lend themselves to fun, illustrative treatments. However, they can be tricky to work with. I recently had to call on past experience to get me out of a sticky metaphor dilemma.