Well if Loui doesn't work with Krejci, which like you said it's only 6 games (and i thought he has looked solid with him) then its time to move him. Doesn't work well with Bergeron, 3rd line? It's that or trade, and he's too good for the 3rd line.
I think they've looked very mediocre,the Krejci line is averaging about 4.5 shots on net ES per game with Loui. Hopefully,Claude simply sticks with it. I'm reluctant to throw any blame at Pastrnak (underperforming as a 1st liner in his second year) or Koko,but there is that.