This is largely personal opinion as someone who uses Next at work all day. But Svelte/SvelteKit or Astro are my personal goto's/favorites outside of Next. Both are robust enough to handle pretty much anything you throw at them, add a complier to help catch errors before build time, and most importantly have incredible developer experiences.
[Astro](https://astro.build) is a production-ready alternative to Next.js and has been giving me great results.
You can render simple HTML/CSS/JS snippets where required, and go all the way up to Svelte/React/etc TSX components without ceremony when you need more complexity.