Taking a look around the league at playoff time is dangerous. It leads to folks wanting to build exactly the way other teams are built. All kinds of talk about the "LA model," "Chicago model," and the Pittsburgh model."
However, I think it is important to see trends for what they are. That's what I'm interested in, and watched games closely looking for them. And I've noticed a trend in scoring lines.
Disclaimer: I'm using the term "3rd line" though I don't believe it's a good term. As soon as one uses the term "3rd line," a lot of folks think Mike Peca, and the checking line from EA sports NHL game. I agree with Scotty Bowman - don't number your lines, just refer to them by the center. But for simplicity in writing, I'll use the term "3rd line." I do not think at 3rd line is a checking, defensive, or otherwise different line than the "1st line" or "2nd line."
Look at Anaheim, Pittsburgh, and Ottawa. What's the similarity? It's putting an actual scoring threat on the third line to create depth. The Pens did it last year with Kessel on the third line. Chicago has done it in the past, moving Patrick Sharp to the third line. LA had Mike Richards on the third line.
Pittsburgh: Kessel or Hornqvist has been with the third line with Bonino almost all playoffs. See how important Hornqvist has been. Traditional non-1st liners with Crosby and Malkin.
Anaheim: Rakell and/or Perry on the third line with Vermette almost the whole playoffs. Rakell has been there more. Traditional non-1st liners with Getzlaf.
Ottawa: Pageau as the third line center, and he's been very effective. Ottawa is a rare team that has a traditional top 6, but with Pageau as the 3C, they have tremendous scoring depth.
Take a look at how their opponents reacted:
Washington: Ran a traditional stacked top six, and a traditional bottom six. Moved Ovechkin off the line with Backstrom, and onto a line with Eller, for game 5. Created three scoring lines. Burakovsky added needed puck retrieval and possession skills to the Backstrom line. Won their next two games.
Edmonton: Stacked their top two lines for the first five games. Broke up McDavid and Draisaitl for game 6. Immediately destroyed Anaheim. RNH and Draisaitl played with good wingers, McDavid played with more ordinary wingers.
Rangers: Stayed with a traditional top 6 and bottom 6, though the Hayes-Grabner line was good.
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The teams that stay true to three scoring lines (Anaheim, Pittsburgh, and Ottawa) often had non-traditional top 6 players with their top centers:
Anaheim had Ritchie and Eaves with Getzlaf. Those two wingers were able to battle for the puck on the forecheck, which created a lot of time and space for Getzlaf. Getzlaf didn't need great wingers to produce. He needed wingers to do the dirty work. Buffalo needs to take a look at this method for Eichel. Eichel doesn't really need great wingers, he needs big, fast wingers who can get the puck back to him in space.
Pittsburgh has Sheary, Guentzel, and Rust with Crosby. Fast wingers with great hockey IQ who could go get the puck for Crosby, then know where to go to receive a pass.
Ottawa is alone among these teams, putting traditional top 6 wingers with Turris and Brassard.
Only Nashville advanced without this forward line construction, but they have the unique top 4 defensively. Which, in my opinion, is a lot harder to replicate.
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So, what should Buffalo do?
I think it's obvious: build three scoring lines. And with the center spine or Eichel, O'Reilly, and Reinhart, they are in perfect position to do so.
As previously mentioned, the Sabres don't need to go acquire a winger like Duchene or skilled winger to play with Eichel. He'd be just fine with lesser wingers. Eichel needs wingers to go get the puck along the boards, skate with him, don't rely on having the puck on their stick, and help on defense. Wingers that could play with him are Girgensons, Baptiste, Bailey, and possibly Carrier.
O'Reilly is easy to build around. He can make up for defensive issues for the wingers, and can play both with or without the puck. He's not produced with Kane, and I don't think Okposo is a great fit, since Okposo needs the puck a lot. Other than that, build with whoever.
Reinhart is fairly easy to build around. His wingers are best as bigger, faster wingers who create time and space for him. He'd also be good with Okposo, since Reinhart doesn't need the puck a lot to be effective.
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I think that having scoring depth over three lines is the way Botterill, the new head coach, and the Sabres need to approach the team's construction. It's clear that teams with three scoring lines playing another team with traditional top 6, bottom 6 construction had the advantage. I'm not posting lines, since that's what everyone will gravitate to. But my thoughts above are what the team needs to be thinking about when building lines. Washington and Edmonton are very good teams that got beat by teams because they could not match their scoring depth, until they finally created it themselves.
No reason to trade Reinhart. Use Kane, 8OA, and free agency to rebuild the defense. Ditch ideas about stacking a top 6, unless the team has 7 actual top 6 forwards where the 7th forward can drive the third line. Time to get in line with NHL reality.