They don't need a new defender right now, maybe when Zinchenko or Tierney leaves bit right now? Tomiyasu and Jurim Timber are good options. Having said that, I do think they had the best defense in the Premier League Competition last season as they did dominated nicely with the partnership of Ben White, Saliba and also Gabriel.
For the midfielder's, they need a replacement for Thomas Partey whether he leaves or stays, Arsenal cannot make much mistakes with letting him go when they have got no good replacement for him. They should also make good use of Fabio Vierra he is a good midfielder and can also be used on the right wing in the absence of Saka.
They should be seriously looking to sign a player who can give them 25 Premier League Competition goals. If they can get that, winning the Premier League Competition next season is a must.
I agree Arsenal defense is strong with Tomiyasu and Jurim Timber. Ben White, Saliba, and Gabriel worked well together last season. But midfield needs attention. If Thomas Partey leaves or gets hurt they need good replacement. Fabio Vierra can play in different positions, which is helpful. Arsenal also needs a striker who can score many goals 25 in the Premier League. If they get that, they have a good chance of winning the title next season.
Khvicha Kvaratskhelia the player of Napoli, has had a good performance so far in the game he played for the national team but now it seems Khvicha Kvaratskhelia is very close to leaving Napoli as he said before he is not going to keep playing in Napoli anymore and he was even linked to teams like Real Madrid, Barcelona and now PSG.
But it seems now after Conte joined Napoli he wants to have Khvicha Kvaratskhelia in Napoli for his team and he made it clear that he won't let Khvicha Kvaratskhelia leave at all, this can be bad news for PSG as they were about to hire this player.
Things have changed at Napoli since Antonio Conte joined. Khvicha Kvaratskhelia played well and big clubs like Real Madrid, Barcelona, and PSG wanted him. It seemed like he would leave Napoli but Conte wants him to stay. This might be bad news for PSG but it shows Conte plans for Napoli. If Conte can keep Kvaratskhelia it would be great for the team and a big statement for next season.