Okay... most of the ones I had in mind for "musically well" aren't as modern as those two, and are far from the same category as those as well as what I listen to regularly.
Nor would they be exactly considered the "peak", as they are old classic folksongs, from youth like Arik Einstein or Naomi Shemer, Yoni Recter... but with the exception of Shotei Hanevua - Yedia, and a few Kaveret songs. Namely Goliyat, Shiur Moledet, Hora Achazut, and especially Habalada al Arivaderchi.
As for the folk songs... Od Lo Ahavti Dai, Ze Hakol Bishvilech, Mashiach (well, it's fun to play it all fancy and stuff), Noladeti Lashalom... and the rest of the list would be way too big, but those are pretty high up there in my book in terms of musically well.
EDIT: Are you serious about Sarit Hadad? Last I heard she wasn't that popular.
~Zak