Ive been raising Mollies, different Killifish species and different marine/Euryhalline shrimps, as well as, pods of all sizes, and some phyto for these little ones. I prefer to receive all of the fish in full freshwater, then acclimate them to Saline, then put them through a QT process, then allow them in to various MacroAlgae tanks, LR tanks. Same with Lysmata sp. Shrimps, especially "peppermint" which seem to be relatively cheap, as low as 3.99 around here. Tough to get them to spawn though. Everything listed above spawns regularly. All sorts of great live foods constantly available throughout my system.
As syrinx stated previously, I wouldn't expect this to fulfill my fishs' dietary needs completely. PE Mysis seems to always be irresistable, and if not, I'd check your fish for internal problems.
Im not exactly possitive about Mollies and fat content, at the moment. I know they are far better than freshwater feeder fish. Not sure if a steady diet is a good idea or if it will lead to fatty liver issues and/or thiaminase. Etc.