To be quite frank KDB isn't really Pep's type of player. He's quite wasteful with his possession although he's better now after with Pep. And he takes a lot of risk.
BUT Pep needs KDB's quality and his delivery of the final ball. Remember Thierry Henry mentioned something about Pep telling his team that his job is to carry his team to the final third of the pitch, and from there the players are on their own and they are free to play however they want in order to score. This is where KDB comes in. His final delivery in the final third is second to none in football (except Messi). Not to mention his ability to score goals there as well.
So in the end we have Gundogan and Silva dictating the possession, and KDB will continue the job and try to pick that final ball to Kun.
Anyone who thinks KDB is not a shoe-in to start is crazy. KDB would walk into Barca's, Bayern's, and Madrid's XI.