I don't think they lost a position in top 4 to Tottenham because their attacking system is bad. In late phase of last season, their young players could not control themselves and could not play well under pressure of themselves and from Tottenham. It is the first season Arsenal was very close to top 4 in last 5 seasons or more. Pressure is big and they failed to protect the fourth position in last 2 match days. They lost it to Tottenham in last 2 match days and it's too late to do anything.
Yeah that was a dropped opportunity and honestly don't wanted to get those memories back again (damn you had). I think we lost that grip in the last 3 matches (I think 3 matches previous to last one). We had striker problem with Laca not being that productive as we needed him to be. This season we have Jesus who is the perfect "fox in the box" and I have huge hopes from him. But PL is a long run and we can't talk about injuries and so so any injuries to our main player can bring us back into same position like last season.
Not gonna demand much but as long as Arteta brings back us to a solid squad like Liverpool or City, I am happy because I know at some point we are gonna have hell of a season with consistent performance like City and Liverpool does or maybe win PL at some point.