I think you have lots of good options here. You asked earlier what you give up with f/2.8 and f/4. It's really just shutter speed. You want to keep your ISO around 3200 or below, depending on your camera, (I was selling prints taken with the 1D X that were ISO 25600, so obviously 3200 is an approximation) and your shutter speed at 1/1000 or faster. Only go below 1/1000 if you are trying to do something cool like blur a pitcher's hand, or pan with a running back so the running back is in focus but all the scene is motion blurred around him. The f/2.8 makes all that a lot easier to pull off, as well as giving a nice bokeh separation of the subject from the background.