The workhorse lens in my collection is also the least expensive and the one I've had the longest. It's the Nikon 50mm f/1.8 prime lens. It retails now somewhere ...
Central sharpness is very good at f/1.8 and f/2, excellent from f/2.8 through to f/5.6, very good from f/8 to f/16 and fair at f/22. The edges are good at f/1.8 and f/2, very good from f/2.8 to f ...
Bokeh is relaxed and pleasing to the eye, and 50mm lenses, certainly fast ones, do benefit from the ability to throw backgrounds out of focus. This is especially useful with portraiture.