We need rotations this game. Starters are coming after 2 matches in 3-4 days. We need to see Malcom, Vidal and Alena. Two of those have to start, one has to play some good minutes. Alena for instance can play 20-30 mins if things are looking good.
Rafinha has played quite some games lately and did it poor (one of the worst). Denis is not good enough. Rakitic needs rest.
Things are starting to settle, and Valverde needs to see the sign, interpret them right and grow a pair of balls to fully use the strenght of the squad to keep everyone (as much as possible) fresh, motivated, and somewhat happy about minutes distribution.
We have a clear first 11 at this point. It is:
Stegen - Roberto, Pique, Umtiti, Alba - Rakitic, Busquets, Arthur - Coutinho, Suarez, Messi. This is our clear first 11 be it 4-4-2 or 4-3-3 or variants.
We then have 6 players of great quality that can play well no matter the opponent. Almost all of them are young and can grow even more. Those are Lenglet, Semedo, Dembele, Malcom, Arthuro Vidal and Cillesen (his case is difficult though, as you can't really rotate them like the other players).
Valverde simply needs to find a way to give all these 5 players consistent minutes. I don't care how he does it, but he just needs to. Each and everyone of these players have proved to have the ability to play in this team.
This is basically our core. 16-17 players who can step in as starters at any time, as long as they register consistent playing time and aren't mismanaged. These players can, if managed the right way, reach big heights, maybe even a treble. Why not? Coutinho is world class, and Suarez and Messi seem to me the best 2 forwards in the game today.
After these 17 players, the next player who should be playing is absolutely Alena. Only after him should Rafinha, and Munir get chances.
Seniority means jack shit. What you need to do is give time to the players who show they have it. Alena, every single game he played for the first team almost has showed he has buckets of talent.