#5 Arsenal
Under Unai Emery, the Gunners have looked a lot more attractive, and the desire to win games is evident. Watching Arsenal break the shackles from the Wenger era and now become a genuinely dangerous side is an excellent sight to behold. Though they have some great strengths, like rivals Chelsea, their biggest weakness is their defence.
The defensive problem at Arsenal though is way more serious than Chelsea as the Gunners' main objective in most games seems to be to outscore the opponent without being too concerned about the defense. This style of play reminds me of Liverpool during Jurgen Klopp's early days and though that system was immensely entertaining even, the Reds sorted out their defensive problems eventually.
Arsenal needs a Centre-Back or they need club captain Laurent Koscielny to recover quickly in order to bring some calmness to their chaotic back-line.