First of all, Smith is our leading receiver threat and most talented WR at that. His job is not in jeopardy unless he has some other issues going on like his attitude which has been spotty at times.
I'm not sure about this L. Kelley thing. He hasn't even seen the field yet and I don't know if he has anything that will separate him from Verlin Moore, Marlin Miller or Aubrey or Falgout (who played well last year) so that may be a bit premature.
Johnson, assuming he commits, would be an invaluable addition to our team. He may not start at WR at first but he'd be used on special teams and different formations when we may want to spread the field. I'm just not that optimistic about his signing.