I think you have to move on from Boeser. He looked great last season, but the Jeannot hit has really affected his game and a long term contract could age horribly. We have Lekkermaki in the wings to naturally take his place, although that will likely take a few seasons to actually happen. Trade him at the deadline and get a good asset or two in return.
He'll be remembered as one of the few bright spots of the Benning era, the first star to breathe life into this city as the Sedins were retiring. I will always feel like his career was dramatically changed by the Clutterbuck hit into the open bench door...if you watch his rookie highlights, he was an incredibly dynamic player that could skate with power and his shot was one of the best in the entire league right out of the gate.
Still a hell of a player, but I think he could have seriously been on the Stamkos/Matthews tier were it not for that back injury.