I have seen great tanks with MM, skimmer & skimmerless, (the skimmer tanks looked cleaner), they was running over two years with the MM. I like sand myself, nothing wrong with it, I don't like a dsb’s anymore just because of the looks, & a remote dsb isn't worth the effort IMO.
The MM is replaced in portions & if kept up should work out nicely, you want dead slow water movement through the area, & you don't want to stir it up. I like the stub addition I saw in the IAP thread, it suppose to slow down the crashing waters. MM has a very through web-site, If your going this route I would thoroughly read & understand their system with design in mind, it will work best that way. The Mud system is a little different by design I would refer to the site for design in this case. I think the rubble rock would be a trap also, take it out IMO, I keep trying that & can’t avoid the trap, I had overflow water dumping directly on it & it still was a trap, let the Mud take care of that.