Niasse is a late substitute sort, can run at tired defenders, send them into disarray and maybe poach a goal here and there. Vaughn did this pretty well in his later time at Everton, AJ, too. Anichebe a bit. Hell, Straq probably would have done okay with it had we been desperate enough to keep him around.
We'll continue to rotate depending on opposition. We have three strikers are the club all on 5 goals so far, which if you extrapolate over the season gets them all well into double figures which isn't bad at all really. It's behind that where we fall down massively.