While I agree (to a degree) with the "CLT is better than it's parts" idea, I also think that might be a thing of the past. By that I mean I believe all 3 have grown a lot as hockey players by playing big minutes and having more responsibility. Also I rate Copp. He seemed awesome fit with Scheifele and Laine during Laine's rookie season for the half-a-game he played there before getting injured... talk about small sample sizes... but also last year Laine's streak of awesomeness started with Copp as the center, until Stastny was acquired.
I believe both Copp and even Tanev could probably work as "the 3rd wheel" in a good first line. I kinda miss having Armia in the roster because he was very versatile and gave options, but that's bygones. Anyway I don't think CLT should necessarily be treated as off-limits. I'd probably rather break up CSW though - I think as a line it's a bit overrated. Yes, it's a very good hockey line, but it creates problems elsewhere with the roster. Also remember what Scheifele-Laine looked like during Laine's rookie season? It didn't really matter who played the other wing, be it Ehlers, Copp or Perrault (though Perrault probably looked the best there) - they are both better hockey players now than they were back then. As good as CSW we looks, it's entirely possible CSL or ESL or PSL would be even better.
Simple option 1: just swap centers
Ehlers - Scheifele - Laine : get Ehlers going and show both him and Laine they are part of the plan, not just by words but by action. This line should be lethal and all 3 have improved their defensive play since we last saw this line
Connor - Little - Wheeler : get Little some help in a familiar face in Wheeler, also I think Connor would work better with him.
Option 2: bring out the blender
Ehlers - Scheifele - Tanev : put that motor to work!
Connor - Little - Wheeler : I guess I would like to see what Little could do with these two
Copp - Lowry - Laine : maybe not, but who knows
I seem to forget we even have Perrault. What happened to him, he's been looking horrible for so long. No effectiveness what so ever and he doesn't even really seem to have the Perrault magic anymore. Or maybe that's just my eye-test failing me.