Between Binns and Matthews, it comes down to if Binns can stay healthy and if Matthews shows the consistency to take advantage of his talent.
Another factor that could affect Matthews and Binns is if we keep a faster WR that can return kicks. Their skill sets may be too close to Gibson and Landry. I'm a little concerned that only Wallace can stretch the field. I would love to have a 6th WR that can take kick returns to the house.