Actually Al-ahli also has many foreign players in their squad. Because last season they were also quite active in hunting players. But the quality of the players brought in by Al-ahli is not as good as the players brought in by Al-Nassr, Al-hilal and Al-ittihad. So I also have the same thought that Al-ahli might be able to continue to compete well at the top. But I also doubt they are in contention for the title. I think the title fight will still be between Al-hilal, Al-nassr and AL-ittihad. I see that Al-ittihad is quite active in adding new players to their squad in the current transfer market.
Al Ahli performed well last season with the foreign squad they have even better than Al Ittihad they managed to finish in 3rd position in the standings last season but this season Al Ahli seems to have difficulty competing in the Saudi League and has even experienced 1 defeat from 2 matches they have played so I also think the same as you that Al Ahli may not be able to surpass the abilities of Al Nassr and Al Hilal in the hunt for the title especially this season the arrival of the promoted club Al Qadisyah where they recruited many foreign players who seem to be going to make a breakthrough this season. In terms of squad Al Nassr and Al Hilal are still the most superior in the SPL but in my opinion Al Hilal is still a very tough rival for many clubs in the SPL.