Emil, you're welcome. Oum Kalthoum is my absolute favorite in Arabic music, and one of my absolute favorites, probably second only to (the very different) Sun Ra. I've probably mentioned her before. I tend to prefer her work from before the 60s, but I think the beginning of Baid Anak (also from the 60s) demonstrates more about her artistry than "Enta Omri" (at least in any realization of it that I've heard--I haven't clicked on that youtube link to see if it's unfamliar). Her earlier recordings allowed more room for her to improvise, but I think you can see her ability to seize the moment in this opening section of Baid Anak:
I am actually the world's greatest
pseudo-expert on Oum Kalthoum.
Oh, incidentally, I recommended that Bachar Mar-Khalife because of it's connection to prog. and electronic music. I didn't even realize you were interested in Arabic music, or had lost track. As far as Marcel Khalife goes, my favorite work remains
At the Border from the 80s. I don't generally find his instrumental work very satisfying, or even enjoyable, and he's devoted a lot of energy to that over the years.