Yeah, the bit that's bad world-building is that they have these terrible values which are repeatedly shown not to work, and yet simultaneously they have a successful interstellar civilization.
What? Like our values? The Ferengi are developed to be every bit as unique, individually, as we are. We see Ferengi scientists, murderers, reformers, inventors, and leaders.
I think it’s more your lack of imagination that’s the issue. The Ferengi are totally plausible as scientists, inventors, and explorers. Nothing they do is at all out of line with what Europeans did in the age of discovery, apart from slavery. The Ferengi never tolerated slavery.
Ferengi females were arguably slaves since they had so few rights.
I think that speaks highly of the Ferengi social system.