The bolded makes total sense, but moving your young improving players that are still under team control, especially the ones that are the brighter parts of a lacking roster, makes zero sense. It's baby with the bath water stuff. As for proven playoff performers...there aren't ANY on the roster so singling out Mitts, Joker, and UPL is just not making any point at all.
The players they need to move on from are Olofsson, Jost, Krebs, Okposo, Girgensons, EJ, Clifton (or slot down anyway), and Comrie. Use any of the redundant prospects like Rosen, Savoie, Kisakov, Neuchev, and picks to get proven vets and/or gritty wingers that can add a forecheck to the skill they already have. If a great player becomes available and that team INSISTS on a player like Mitts or Joker going back, then you think hard about it. You don't go looking to move them first.