Barcelona made it pretty clear that they're dropping tiki taka for a much more fast-paced passing game that doesn't have the free moving style of tiki taka. They sold Fabregas, Xavi is likely to leave and they signed Rakitic. I think they're gonna go for a 4 steady defenders, 3 steady midfielders with one acting as a defensive midfielder and three attackers, two of which roam around freely and controlling the attacks. Wing backs will support these free players by moving up and down the pitch and two of the center midfielders will apply pressure.
Messi played best as the center forward because as the False 9, he was the target and essence of every Barcelona attack. You can't play a False 9 at wing. Messi is a player that is capable of producing assists and goals from wing moving to the center with the ball. Actually, his strongest shots are ones that come from right wing and hit with a finesse shot to the opposite post with his left foot.
Suarez is a player that constantly moves around, unlike Ibrahimovic. Ibrahimovic didn't fit in because he's a steady player which has absolutely no value in a tiki taka system or a constant passing system.
If they do sign Suarez, I'd expect them to play like this (They desperately need a world class center back to play instead of Mascherano):
I agree, however, that Suarez is a much better fit in Real.