I believe Arteta will have to look into this matter if they really want a good performance because the best players can’t cover up always for example injury might come at anytime besides they’ll not only face little team but the big teams as well.
Signing new players is very important and all teams should do it. But what I see the problem that Arteta really has to pay attention to is not just continuing to bring in new players but implementing the right strategy. Now we can see how many times Arsenal almost got the EPL title and one step closer to the title. The fact is that every time towards the end of the season Arsenal always lose consistency and productivity decreases. So quite simply Arteta's job at the moment, bring in quality reserve players and implement the right strategy to focus on one of the important competitions.