Arsenal players are good no doubt, it doesn’t really show if they’re lacking a striker seeing they don’t get the negative impact as much. Honestly they’ll have to make more signing this summer including a good backup player, searching the net for a good information nowadays is complicated and viewing their official page no signing for now but, 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.
It is true that no players have officially joined Arsenal in this transfer window only a few players return after their loan period ends, but we know some of the players that Arsenal targeting and in negotiations, for example PSG player Joao Neves has attracted interest from Arsenal at's just that we don't know how serious Arsenal are about him and the market price is also expensive, around 80 million.
Arsenal is always slow to things like this. I don't know the plan of their management and which players they want to sign. It's clear that the players that they already have in the club cannot win the EPL title after four consecutive attempts. The need of a few new players to add to the team is very important for a stable performance throughout next season.