Primarily, low stocking levels, very strong filtration, good water flow, and frequent water changes, should take care of algae problems, without the need for a CUC. I would definitely implement some type of nutrient exporter, such as a refugium or turf scrubber. And strongly consider an ozone unit, and maybe a large UV unit.
As far as what critters are safe with what fish, we would need to talk in specifics. There is such a variety among wrasses, triggers, puffers, etc. Some guys are usually somewhat possible with aggressive fish, Cowrie Snails, Olive snails, and coral banded shrimp.