If we keep Karlsson, I'd bet they are thinking they've got Ceci and Chabot who can play 22 minutes a night away from Karlsson, and because Karl is so good, they can fill the left D spot beside him by commission while Karl plays 27 minutes a night.
If Chabot+Ceci are one pair and are always together, similar to Ceci+Phaneuf, then we have Harpur, Wolanin, and Borowiecki all splitting minutes next to Karlsson.
Harpur is the closest thing we have to a D on the left side who is NHL ready and might be able to be the conservative stay at home guy next to Karlsson. But he's a huge question mark as far as whether he can play at the level needed to maintain that role.
Harpur doesn't really cut it as 65's partner. That pairing can really use a Methot so that EK can dictate/join offense. Harpur is not a 20 mins a game player, more of a rotational guy as the 7th man.
I have decent hopes for Wolanin, but his game isn't suited for the Methot role.
Crime Master Boro shouldn't play more than 3rd pairing minutes, and he plays those minutes tough. Boro can be very effective playing hard shifts in 16ish minute TOI.
To begin the season, I do see different EK partners to start the season, but with these guys it seems futile. I hope Boucher can come up with a plan to device a game around Karlsson and a non shutdown guy (like the rookie Wolanin) to stabilize the first pairing with the types of assets available.
PS: Wolanin-Ceci is a disaster waiting to happen. Chabot-Ceci may work with some initial pain. Wideman-Boro may work fine (with a bit of pain) if Wideman is fully healthy and gets his form back quickly.