Um no. Even if Nash is better right now skill wise, his age and injury prone body will lead just being on the team.
Marshall, maybe. I just haven't seen much from Marshall to tell me the Lakers want to stick with him long term. Them drafting a PG would point to that as well. Marshall put up some solid stats but the Lakers were generally getting destroyed so most of his points (8 PPG) came in garbage time and his assists too (8 APG).
So let me guess, you also believe that Diante will start over Kyle Lowry(even though he is going to be cut), Royce will start over Boogie Cousins, Ejim will get more playing time than Leonard, Babb will start and get 30+ min for the Celtics and Stevie Johnson will leave Euro ball and be the MVP of the NBA next season too??