I have said it before and I am happy you are reasoning my way. Arteta should not risk this great opportunity to lift the English Premier League. Arsenal doesn't have a good squad depth to win both the Europa and English league. I am not saying that they should deliberately crash out of the Europa League but I am saying that Arteta should give more priority to English Premier League than Europa league in terms of player selections and concentrations.
Preferring the Premier League doesn't mean Arsenal have to forget the Europa League, because as long as Arsenal are able to get good results for both of them this season, it won't be wrong to do so even though it won't be so easy for Arsenal. But I see that there are better developments in the Arsenal team this season so that Arsenal will definitely be able to fight for those two very good trophies (the Premier League trophy and the Europa League trophy).