There is a benefit of Jones over Koekkoek, but for a bottom pairing guy I prefer Koekkoek, especially for these playoffs.
I feel like against the intensity of playoff opposition, where even lower teams will up their tenacity, Jones could get badly exposed. Jones' skills are useful in that situation too, but considering our D and team in general, we should opt for stability over aggression for our depth D, and leave the gambling for Barrie, Bear, and Nurse. Or even Kulikov and Larsson.
Plus that bottom pairing will have either Bear or Barrie on it. You want the other guy to be a responsible veteran like Koekkoek or even Russell.
But I do support Tippett giving Jones so much rope. I think he will be a solid option to change the look of the D if we want to, and perhaps even to draw in the odd game to be a puck moving D who is also fresh.