Any line with Z and D can't get down ice - neither gets skating down ice fast enough and the play goes side to side. Doesn't matter who you put with them.
Okay I disagree with you those guys still get down the ice maybe not with pure speed but pav can still break in the zone fairly easily, z does it more with strength, and I believe those two will get better they always take a game to get adjusted to playing with each other again. I think mantha would be the perfect fit with them. Not every line has to be fast those two are smart enough and can make plays that they don't need pure speed. Then your 2nd, 3rd, and 4th lines are pretty quick