We have too much finesse in the middle, and not enough function. Three Hendersons behind a Coutinho-Suarez-Sturridge triangle, or two behind a front four of Suarez-Coutinho-Moses, would probably work better than what we have now. The balance isn't right, and Rodgers will live or die by how he addresses that problem.
That's it, isn't it? Not enough function.
We're talking new players, aren't we?
I must admit I'm drawn to the kind of solution Rafa had. Close zone 14 (or is it 5 outside our box?) with the CMs. I can still remember a CL game where we closed that area all game. When I think of those pictures earlier in this thread, it's a huge difference.
However, I also recall that you have mentioned that Rodgers plays with a rotating(?) CM, where players are not locked to one specific role, which they were under Rafa. If we go with the current idea, I find it harder to specify what type of player we need to address things.
I reckon it would have to be an allround player, better than what we have and ideally we're talking a defensive midfielder/attacking midfielder. The complete package. He'd be our best CM. That's where I end up. A younger Gerrard or perhaps Yaya Toure come to my mind. I don't want to turn this into a transfer thread, my point is I think we'd have to find a top class player to fix our current problem, sticking with the same ideas.
If I was to go with more "locked" roles, I'd imagine that we'd simply say that Coutinho and Gerrard are the attacking CMs in that 4-2-3-1. They share that role and Coutinho is now number one. Gerrard being Gerrard, he could also come into play for the "2", but primarily as a backup. Gerrard would basically fill in where there's an empty spot. Lucas is the only defensive midfielder we have and that's a weakness in our squad.
Right now I think we'd use Lucas-Henderson for the "2", with a medium-term idea being to bring in another defensive midfielder. Henderson essentially being the new Sissoko. A source of energy, but in the "2". I reckon Rafa would see it as a luxuary to have Allen, Henderson and Gerrard share one role behind Coutinho and beside Lucas, with no other defensive midfielder in the squad. So one of them off and a new defensive midfielder in. Giving us Lucas, Coutinho, Allen/Henderson, Gerrard and Another.
But we'll go with the first alternative...