It is impossible to replace what Ellsbury brought to the table in 2013 with the Red Sox current personnel, and in fact with the personnel of most major league teams. Ellsbury being so successful on the bases while being on them enough to matter is a rare combination. If the stolen bases by themselves were so important you go and pick up a Rajai Davis or a Jarrod Dyson. So in general I think Ellsbury's value last year goes underappreciated.
Luckily for the Red Sox, there are other ways for players to achieve that value. JBJ may not create havoc on the bases, but he should hit for a bit more power and his defensive game is better at similar points in their careers. He still won't be as good as 2013 Ellsbury in 2014 unless he has some kind of giant step forward, of course. So also luckily for the Red Sox, they don't need him to be, they have other positions around the diamond where they can make up those gaps.
All of that said, to the question at hand, it's still April. If everyone is healthy I think JBJ and his options remain the odd man out. Not that wins count more later, but the information you have increases with the passage of time. I'm not sure it is worth cutting guys right now just to preserve JBJ's place on the team. Although to be honest I would ride his hot streak into letting Victorino get a nice long rehab and strong medical report.