It’s unfortunate but the component library situation is really Svelte’s weak point currently.
At Monitoro[0] we bit the bullet and implemented the vast majority of our components from scratch. Apart from the obvious time to develop and test, and the trailing bugs that are hard to solve for small closed source projects, the experience wasn’t that bad.
Ultimately what helped us the most is writing our components using a state machine-like pattern, mixed with TailwindCSS to make styling easier.
In our case, the effort was worth it as we anyway needed several super specific components, and now that we’re over the hill we have complete control on our UX.
(Also having built component libraries/design systems before in different UI frameworks, doing it in Svelte was one of the best experiences so far)
There are some efforts in the Svelte ecosystem but they’re small and do not have much firepower behind, thus limited or of relatively low quality.
[0]: https://www.monitoro.xyz