Al Hilal always gave the impression to be a better built team compared to the other ones. The don't have any real superstar but they have many extremely good players in all roles. Al Nassr is all about Ronaldo, and this is both a blessing and a curse. I also like a lot Al Ahli because despite the limited amount of foreign players they obtain excellent results. To be honest at the end the most disappointing team has been Al Nassr, everybody were expecting them to win everything and they ended up with nothing.
Sometimes you don't need superstars to shine as a team, just like you said, they have many extremely good players in all roles, that alone is enough to make a team unstoppable. Just have players that are good in their different positions and you're good to go. Last season Al Littihad were so good that they beat both Al Hilal and Al Nassr, infact there was even this very match that Al Nassr were leading with 2 - 0 but at the end, it ended in Al Littihad winning 3 - 2 on the night.