Здравствуйте, Lazy Bear, Вы писали:

LB>Что есть "красивый GUI" в вашем понимании?

В моем, например, такой:

https://dribbble.com/shots/11413070-Background-Check-App
https://dribbble.com/shots/11635146-Automated-data-capture-from-invoices
https://dribbble.com/shots/11959906-Dashboard-Subscription-Report
https://dribbble.com/shots/12873820-Dota-2
https://dribbble.com/shots/12218157-The-All-New-Performance-Graph
https://dribbble.com/shots/12241210-Banking-application
https://dribbble.com/shots/12517549-GIVE-YOU-CASH
https://dribbble.com/shots/12916731-Card-swipe-micro-interaction
https://dribbble.com/shots/12025415-Exodus-Wallet-2-0-The-Local-Transitions
https://dribbble.com/shots/12259946-Meeting-AI-Emotion-Recognition
https://dribbble.com/shots/12578692-Dashboard-Hospital-Status-UI-Animation

Но эти интерфейсы не для программистов, а для обычных людей.

А так же:

https://discord.com/new
https://www.adobe.com/products/photoshop-lightroom.html
https://store.steampowered.com/
https://www.fabfilter.com/products/pro-q-3-equalizer-plug-in
https://www.presonus.com/products/Studio-One
https://new.steinberg.net/cubase/new-features/
Mac OS и iOS целом.