My tank is around 200 litres with no sump also.
Got around a dozen fish, softies, LPS, and SPS corals, and an anemone.
So you have plenty of options but doing it like this a quality skimmer is a MUST, or the tank will get mucky and turn green. My particular skimmer is a Deltec HOB ( Hang On Back ), but any good skimmer will do, this is contraversial but, in my opinion only, a needlewheel skimmer is the best way to go.
Even with limited lighting, there are some beautiful soft corals you can keep. I have a small tank in the garage with no light at all other than what comes in the window, and mushrooms growing happily in it.