We went semi permanent with reef-safe concrete holding the bigger rocks together. Just don't expect to do it in a couple of hours on the day you fill your tank. It takes time and planning, and probably a few zip ties. You will want to somewhat blend it into the rocks to get a more natural look. You don't have to overfuss, though, because it'll get covered over with coralline and stuff fairly quickly.
Having drystacked, as well as trying rods and pipe, this was the only way to go. Drystacks are a royal PITA, and they can fall down very easily, demolishing coral and potentially killing fish, nems, or clams. Drilling into rock to place rods? Good luck. Either the rock is too hard to drill, or it breaks into multiple pieces. Hiding pipe? No thank you.