Arteta realized what *his team lacked last season* and now he will perfect it. it's not just Arsenal who will make things difficult for City. I'm sure Man United also has surprises that will make it difficult for City this season. City is indeed strong. but who will play consistently in the League and who will get the trophy.
I suspect these three teams will be the strongest in the Premier League. maybe coupled with Newcastle as a new force that has started to show the results of their hard work last season. and this season they will try to do better.
then how about the teams that are promoted to the Premier League this season? they had to work hard to adjust to competition with much stronger teams.
It's not like what Arsenal lacked but I feel it was more like what we need given the competitions we have to play in this season. We need backup and strong players in some positions which we filled up this time. Hopefully the upcoming will swiftly pass and bring us the success we've been longing for.
As for strongest in PL, I think United, Arsenal, City, Liverpool are strong teams. Throw in Newcastle and Brighton too. Chelsea also might improve a lot this season as compared to last season. Spurs might wobble a bit. About the teams promoted, I have my hopes high with Burnley in PL and I feel that they should finish top 15 at least.