Spice things up a bit

Me and my boyfriend have a great sex life but I want to spice things up just a little to kind of surprise him. I get off knowing that I’m driving him crazy so I’m on top a lot of the time and I make sure to low key torture him. But I only have so many tricks to do that. Like going very slowly all the way out and back in, or riding just the tip for a little bit really fast and suddenly sit all the way down on him. I’ve done these things in reverse as well. What else could I do on top that would take him by surprise and drive him crazy?