Power is a 6'6" do it all defender in the same mold as Pronger or Hedman. Good skater, great slapshot, physical, very good first pass and plays pretty good in all 3 zones. Low end potential is Colton Parayko - solid #2/3 option, PP2, PK1 type. High end potential is Hedman if he can continue to consistently develop his overall game, allowing for his offense to be a byproduct of his defense.
Clarke is more offensively dynamic, though I think they'll end up with similar production in their careers. (50-60 point guys) Good, elusive skater moving forward but definitely needs work on his backwards mobility. Very skilled stickhandler, very creative offensively, and can play as a rover/4th forward type. Low end potential would be Dougie Hamilton - #2/3 defenseman but #1PP weapon. Not often on the PK unless you want a shorty. High end potential if he can improve his lateral mobility is EK53.