A team as Arsenal needs to choose their priority as soon as the season is starting so they can achieve one trophy this season as they have been going tropyless for some seasons. Other teams that has been having a bad season are getting crown champions in one tournament but arsenal is getting nothing and this is not looking good for the manager as it will put him under more pressure. Trophy help keep a manager career so he can impact the team and work with them to win bigger tournaments. Arsenal need to start winning trophies and if it needs them to focus on just few tournaments, they should do it.
To build a strong character as one of the contenders in the Champions League is not easy and Arsenal need to make a major overhaul if they want to achieve that. The presence of Arteta has indeed changed a lot of things for Arsenal but the changes have not been completely successful. Talking about the Champions League is not as easy as talking about other leagues because here it uses a different system after entering the group stage. Arsenal need to build a much better strength if they want to chase trophies but before going too far they must first win the Premier League title.
In the Champions League everything is different there are many other clubs whose strength is much better than Arsenal but also have difficulty winning the title. Arsenal who do not have the mentality and experience will be much more difficult and maybe this is what Arteta must fix so that they can be stronger when playing in the Champions League next season.
I think Arsenal doesn't have to make a major overhaul to become champions because they already have a pretty solid squad and a good coach. At most, they only need to sign a few players who are really needed and don't have to make changes on a large scale. Arsenal's real problem is that they still don't have the winning mentality that Man City and Real Madrid currently have, and I think if on several occasions they can reach the final, it will form that necessary mentality on its own.