Welcome to the board from Southern California.
All of your ideas are good, use the ladder, drape some over a table, a mannequin is great for a jacket. A steamer trunk draped with a quilt is good. Draped over a chair, if it is in a place where no one can step on it, you can also put one on the floor. A table with the runner is good, just don't cover it up too much with the dinnerware. If you have a way to use a quilt as a space divider, you can handg two that wayor show the lovely back of one with great quilting.
I'm sure that there are others here that have set up shows and will have some gread ideas.