I agree with everything here. Point #1 is spot-on. Whether he can play baseball or not is beside the point. He's a human being and his personal health is the most important thing. If he can come back and play ball, all the better.
Now, assuming he comes back, I wouldn't be so fast to trade him. His versatility makes him valuable to everyone, including the Red Sox. When utilized properly he's the 5th OF as well as the UIF. He can sub in literally anyplace other than P or C - and the jury is still out on those positions. (Personally I wanted to see him pitch in a situation where the Sox had to use a position player, but that's beside the point). If you want to say that he's not as good as our backup OF - you're right. But IMO when healthy he's as good as our UIF and more versatile.
Yeah, we can probably get something "good" for him, but is that player we're going to get going to help the team as much as having a player with his versatility?