Yeah I tend to agree. If you look at last season, we recycled the ball alot quicker in midfield, thanks to having Lallana and Gini in there more often than not, both can turn defense into attack quickly from deep, so what we lacked in genuine steel, we made up for a bit in that technical ability to get us out of a tight spot. Lallana has been injured a fair bit and Gini has been in the team less, while AOC is clearly there to give us a bit of what Lallana does in that sense, but neither of those three are consistent enough in terms of performance or the ability to carve out openings.
The bigger problem is and always has been, lacking someone who can put their foot in and be positionally clever. Keita sounds like he will more or less replace what we've lost with Coutinho, which leaves question marks over AOC, Lallana and Gini, while assuming Can goes, you have to then wager that Henderson and Milner will be the cover for the two deeper midfield slots. So doing the math, we're getting either a DM or a playmaker, knowing what we know of Klopp, it'll probably the latter, with the Henderson or Milner workhorse alongside it. Not terrible but not ideal in the longterm. But like I say, adding Keita plus another, even if Can does leave, puts huge question marks over a couple of players.