UI pack was created with the goal to provide secondary interactive frontend components that have been through a lot of research and tests. The aim is not to be a generalized design system or component library for a company or project to adopt, as a lot of project teams often prefer to roll their own component libraries, or use one of the many existing ones for frequently used components like buttons, badges, and similar components that define visual theme.
Some components offered by ui-pack are features proposed to be native to the web platform but may not have good enough cross-browser support. To achieve an API design and behavior similar to proposed solutions for the web platform, we keep a close attention to existing implementations, standard proposals, and organizations like open-ui that is made up of industry experts dedicated to research and finding ways to unify how UI and accessibility experiences are made across the web.
With all appearance decisions left to you, the benefit of relying on a network of research is not to have you create interfaces that look the same as everyone else's but to ensure that for each component, the states, behaviors, and accessibility do not differ from what your users expect from using other good interfaces.
We like the W3's rule of least power and hope that the APIs provided by UI pack require very little to no configuration, providing as much little power as can be possible through the API usage while having unlimited power in implementation, customization, and control.