I don’t build any of my action sequences with models, though that’s an excellent question. I have a vivid imagination, and generally don’t need to place things on a map to create an action sequence. In fact, I think doing so might be dangerous, as I’d be tempted to describe things happening across the action sequence all over, rather than what is immediately happening to the viewpoint character—which is where my focus needs to be.
Often, the only map-based worldbuilding I’ll do is a general sketch of a continent or city so I know broadly how everything is related. But then I write the book, and let what has to happen in the book happen—good storytelling trumps cartography. I can always rebuild the map to be accurate once I write the book.
The exception is large-scale battles, like some of those in The Wheel of Time, where I had to involve real warfare strategy and tactics. In those cases, I need to know enough that it’s best to draw it out and have a full battle map.
As a novelist, feel that I need to approach action sequences differently from how movies approach them. In a film you can watch Jackie Chan going through this marvelous fifteen-minute blow-by-blow fight, but I think that in fiction the same thing written out descriptively would get very boring. I can’t compete with movies in that regard. So I try to make my action sequences character-driven and problem-solving-driven, as well as how the magic system works. I look at what resources the character has, what they are trying to achieve, who they are and how that influences their actions.