In the broadest sense softies are the easiest and least demanding corals to keep. That being said there are many species that are more demanding, or have completely different requirements than your typical softie.
Xenia for instance can actually be touchy and likes an established tank. That being said it grows like a weed for some and can take over a tank.
My Yellow Fiji Leather actually requires the opposite environment from other softies to thrive- high flow, strong light, and pristine water- more like SPS conditions.
Lighting for softies like shroom, zoas, and xenia can be minimal- CFL on up. If this is for your Biocube, then the stock lighting should be more than sufficient. Flow should be low(not stagnant) to moderate. Feeding is not necessary, but many will benefit from dissolved organics from what is fed to your fish and micro foods like DTs.
Like anything else, read about the specific softie's needs before you decide to put them in your tank. Many, like zoanthids, can be toxic to yourself and others.