You don't trade a likely hall of famer who is still in his prime for an unproven rookie regardless of a top 5 pick.
Troy might be one of the most instinctive and dynamic SS in the history of the NFL. No way...
As far as injuries are concerned, I would move him to FS still before I would even think about trading him.
But realistically, I don't agree with how Lebeau sometimes has Troy just dive into 300 lineman at full speed. Most of the time he just ends up on the bottom of a couple lineman. It's just to risky to play Troy will that much carelessness. I don't mind him playing close to the line of scrimmage, but that routine where we just trys to take out lineman to either eat up a blocker, or whatever it is shouldn't be done.