The current squad is not even competitive enough to compete against Al Nasr and Al Hilal. Clubs need to change coaches as soon as possible. A club's coach, if talented, plays an important role for the club. There are some teams that do not play well for good coaches. Al Hilal is a good team, but it is incomplete without a good coach. So it should be resolved very quickly.
Man, which team do you refer to? Please mention the team first before explaining anything. 
Sure, Al Hilal and Al Nassr are 2 top teams in Saudi league. If other teams want to compete with these teams, they must improve their squads. Al Ittihad and Al Ahli are 2 other teams that have closest level with Al Hilal and Al Nassr. But surprisingly we have Al Taawoun that can finish the season in the 4th place, it is above the position of Al Ittihad.
I agree that the the coaches have crucial roles. Even if Al Nassr has many star players, they can't win the trophy of SPL because the quality of Al Nassr coach is still in lower level of Al Hilal coach. Al Hilal has a great coach, he can make the team to play solidly. Having many top players will be useless if they can't play as a solid team.