Arsenal are always close to trophies and fail at the last rounds due to Manchester City being so powerful these years. Spending money moderately comparing to other clubs while keeping top places and UEFA Champions League spot is something that worth to keep the coach and try again next season.
We will see if there will be much changes in the transfer window in English Premier League teams to expect how the next season will look like.
With the changes from other teams as well, it should be possible for Arsenal to still have a chance to get another trophy next season. But indeed, other teams also continue to make great efforts to be able to have better performance and also make great efforts to be able to maintain it. But unfortunately, player injuries and or the tight match schedule will have a bad impact on the results they will get too. Therefore, preparing players by buying some potential players will also make the team better. After all, Arteta also managed to become a great manager and thus, it seems that next season Arsenal will still be fine if only to compete in the top four.