If Arsenal still have dependence only on certain players then of course, this factor will make Arsenal not compete in the title race. Because after all, last season was also the case when several key players suffered injuries so that Arsenal's performance fell and failed to maintain good results. Therefore, Arsenal should learn from mistakes, and must remain strong and compact even though some of the key players cannot be played. Because only in that way, then at least Arsenal will be able to maintain good performance and results in each match.
They had to think about density and backup for this season as this season they are not only in PL but also in CL. It is very hard for clubs to manage their squad with injuries and all when they have both CL and PL around. We either way needed some backups as centre back. We still might need one but I think as for now it is ok with what we have.
I feel that there should be rotation from time to time so that everyone gets chance and develop themselves. I like the fact that Arteta is giving some chances so I think he is managing it very well so far. I think in next game instead of playing Partey as right back and White as center it will be Kiwior and Saliba at center and White as right back.