I'm gonna be in the minority here, and say that IMO, DS9 did more damage to the Ferengi race tha any bad episode of TNG could ever have (cut)
But DS9 totally killed any semblance of integrity to the Ferengi. The Nagus was a joke, Moogie was a joke, and they took the Ferengi need for profit to ludicrously silly levels... the "Divine Treasury"? C'mon...
The writers of DS9 had one thing in mind only... to use the Ferengi to make us laugh. (cut)
They def. used them for comic relief. And I kinda agree... I don't really get what was up with Rom and the Nagus... but Rom was smarter than his physical limitations- and remember that time he almost jettisoned Quark into space? The Ferengi was in him... somewhere. I understand Moogie as trying to get back rights- because the Ferengi weren't always the way they are in the 24th C. Because of Rom, I see why Nog does what he does.
Quark I find a great balance between comic relief and alway, always being devious, commiting crimes, and going for profit- which he thinks he should.