How is he compared to Caicedo? A less defensively sound better attacking cheaper player? More of an 8 to Caicedo’s 6?
Yeah. They'd be a really nice pair. I think Casemiro and then one of Bruno or Eriksen could play with either. Lavia is weaker but also can slow things down and sees more in possession. Caicedo-Casemiro would be lacking in creativity, but we'd be really fluid and tough defensively, and maybe Shaw, Lisandro and getting the ball out wide in a hurry is enough to compensate.
The right side of defence lacking passing would probably become a real problem, though. You might see Bruno or Eriksen (whoever is the #10) ending up there constantly to link play, though they've both played well on the right of a 3.
Rashford
Caicedo
Shaw
is a nice balance on the left.
Less sure about:
Bruno or Eriksen
Antony
Dalot or AWB or new RB on the right
As a trio, but Casemiro could shade right a bit since Caicedo covers ground well defensively and wants to stay central anyways.