Firstly, I agree that filters are no needed, but I do caution about using lots of live rock. Rock also provides a place for algae to take root and over time can become detritus traps, decreasing its efficiency. And keep in mind that rock blocks flow.
I recently removed about 30% of my rock due to a long term algae issue. If I were to do it all over I would have use just enough rock to mount frags and add more rock for additional corals as needed, while going with a sump for my filtration needs. I have a basket of live rock in my sump but reefer whom I respect for his skills uses marine pure blocks in his sump so the he can swap them out of any start to lose their effectiveness over time.
I don't know if there is some formula to determine how much rock to use. But start slowly.