I've been thinking about a multiple component system. I have less confidence in mixing macro and SPS corals, and or seagrasses, than mixing a nice mangrove colony with seagrass beds.
Seagrass beds are common around the mangroves where I've dived.
Both are strong plant driven communities which goes along with my general theme, with deeper sediments etc. Tidal flux is about 12" 1-2x a day.
Reefs can vary a bit more and can have higher current, deeper upwelling, temp issues, KH/Ca++ etc. Nothing insurmountable, but not as married together as seagrass+ mangroves. There are many species of macro algae that can also grow in conjunction with the these two groups as well.
This guy wanted corals, but if you replace those with Seagrasses, and use some natural light: