I don't watch NFL but from what i hear about running backs, that seems to be the equivalent to explosive point guards in the NBA.
That is: the shelf-life ain't that great (with exceptions) and with the way offenses are evolving it's not really a necessity to have one, unless they're a dead-eye shooter.
I mentioned it last year but from Franchise, Marbury, Baron, Rose, Kemba, Wall, several others... all injured/cooked/needing to reinvent their games by their late 20s/barely 30. Russ has lasted but it was looking bleak until -to your point- other players (like PG) considered him a great teammate/locker room guy.
His off the court demons aside, the sooner Ja develops a Tony Parker game + floater, the better off he'll be long term.