"The House of Quark" was one of my favorite season 3 episodes. The other two Ferengi episodes are on my "Do Not Watch" list.
So I, too, find them of varying quality. When they go for the OTT gross-out yuk-yuks (ear hair! eating worms!) it kind of kills it for me.
It's worth saying that, by the end of "Profit and Loss," I was totally buying Quark as a romantic lead in the Bogie vein, simply because they stayed away from the "humor" and because of Armin Shimerman's delivery.
I'll agree with TheGodBen
that Jake teaching Nog to read was the stand-out moment of the episode.