In 113 PL apperances Bissouma has had 1 red card but 28 yellow.
I think with players like Bissouma, Romero and Bentancur we'll have to accept that there will be a lot of yellow cards. It's the physical component of their game and we don't want to lose it. To compete in the PL we need a few players like that in the team.
An accumulation of yellow cards isn't an issue anyway. We can easily cover a one-match ban.
Red cards are clearly much more damaging but hopefully the coaching staff will coach them into being a bit more judicious about when and where they go in hard.
They could learn a little from PEH. He gives more than his fair share of free kicks away but he doesn't accumulate too many yellows. He's quite canny. He tends to block and impede, and prevent opponents progressing. Enough to give away free kicks but not quite enough to earn yellow.
It's a good blend and it will enable the likes of Son concentrate on the attacking elements of their game.