So, if we move Kravtsov to 2c, that's breaking up Panarin/Strome but having Stone on 3c would be a luxury and will he continue to play well w/o Panarin?
Don't think of it as a rigid 1st line, 2nd line, etc
Think of it as trying to create the most effective combos.
We want to do that to give certain players more minutes
AND
we want to avoid giving coaches, esp likes of DQ and before him AV, extra discretion to make constant changes. [Less experimentation here is better, more familiarity = more comfort = better results/consistency/synergy from best chemistry.]
So first off, we can't afford Strome and Buch beyond the upcoming season even if we juggle. We do have most of next season at this pt to see about Mika. Zib has to do only 3 more yrs past his final sweetheart yr on current contract. If he does that I give him a full 9. I would consider 4 x 8 but no more. I make a single exception for Kreider b'c his history shows dedication to physical fitness and is likely to be in better shape than most in his mid 30s.
Now, we would want max mins for Kakko and Kravtsov to benefit from playing w/Panarin, who could shepherd max them. Kakko already looks good w/Panarin [as do most] and on paper Krav does also.
completes like I say:
driver of play + facilitator + scorer/finisher
Kakko - Kravtsov - Panarin
If you want to consider that our 1st line b'c its Panarin, fine.
Next is young turks
LaF - Chytil - Gauthier
On paper this is also a fit. The Ws reverse the roles as LaF is the scorer and Gauthier more the driver of play w/Chytil as the facilitator.
Like w/the Panarin line, all 3 Fs share all 3 duties, tho one is more of a specialist in each area.
That leaves for now w/
Kreider - Zib - Blackwell [possibly challenged by Barron]
in this case Kreider's beast factor drives play, Zib scores, and Blackwell facilitates.
4th line = open competition and is principally for checking as well as chipping in.
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So to more fully address your ?s:
Strome has proven he can play w/o AP;
how well he plays in other combos depends on what chemistry is with those other F linemates.
Strome and Buch, long term, should be out of the equation for next yr
Kravtsov SUGGESTS he may EVENTUALLY be a good/great C on his own, but for now, both to benefit from synergy AND to max his development learning NHL, and ditto for Kakko, do that KK-VK-AP line.
To extent Strome/Buch are still here rest of this season, play them together as remaining line, 4 or whatev games for Barron to not waste an elc yr, then Rooney or Howden rest of the remaining games.
Yes, pushing Strome/Buch down adds quality depth.
Bruins are successful w/4 strong lines.
But now that they have what they have under their belt(s), the young(er) players above will benefit more from the combos and more mins I suggested.