I agree with you. Arsenal first target should be winning Premier League because that will bring a lot more confidence within club and also raise their morale to actually try and win UCL. That's why , next season I do have Arsenal to win Premier League but also reaching at least quarter finals in UCL ( maybe even eliminating Real Madrid ? ) because this club and their players have achieved a level of maturity that can push towards being champions.
Arteta also knows how to keep his players in full focused mode and I'm curious after Euro ends , he will make new transfers because there are some young players who could play for Arsenal this season.

If we decide to focus to win all competition then we might lose all because their is no way you can chase two rat and be able to catch even one its not possible. So it will be better for Arsenal to focus more on the Premier League than want to win two trophies at once if it is possible. But for now this is not the time for us to want to win the ucl because I don't think we have that kind of capacity now to win the ucl the resources we have are not that strong, if we deploy more strength to the club. How front is not that strong so we need deployment of attackers. We are having to much criticism from other clubs that arsenal is not doing well, we need to clear them that we are better than them what ever club it as to be, they should expect the trophy to be ours next season. Eliminating Madrid hmmmm i don't even want us to focus to much on the ucl, we need to clear Manchester City doubt the fact that they always claim to be the best.
Honestly, Arsenal as a club has all it takes to win any competition of their choice. They have had a formidable squad since two seasons ago but it is quite unfortunate that they have never made good use of this squad. The major problem with Arsenal is planning and focus. It just have to focus on only the Champions League, focus on only the English Premier League or the FA Cup. What I mean by focusing on one of these cups or titles is the ability of the coach to reserve players for matches in such competition. Play second eleven in other competitions and also communicate to the players that their priority is one particular cup or title. Just do this and win something and the boys will be motivated to do more. I am no longer comfortable with the near success syndrome. Although, ending the EPL as second for 2 consecutive seasons is a good record and achievement.