This is exactly why I like to use these UI toolkits, and despise most web "UI" frameworks. That uniformity is why these applications are usable and predictable, and yes, boring. Deviating from the defaults takes effort, and that's a subtle hint that it's something to reconsider. You're deviating from the norm, and that might indulge a developer's whims or the demands of a manager who wants their application to stand out from the crowd. But that superficial difference is something I've despised ever since we have WinAmp and XMMS skinning the UI like many media players, purely to look different at the expense of usability.

Even after reading lots of UI guidelines, and developing several tools and applications, it's taught me that I'm terrible at it, and should let an expert do that part while I stick to the other parts!

Personally I like consistency. I've actually moved away from GUI apps in general because the terminal is more consistent, so I feel like there's less to learn with each new tool.

Yes, I should’ve said UNIX-philosophy or something... what I said was pretty ambiguous. I meant UNIX-style in terms of single purpose tools that work together over a common bus without being tightly coupled.

Not actually UNIX UI libraries.