If you haven't tried Stencil.js, might be worth giving it a go. I found it a dream for working with web components since it takes care of almost all the tooling

If you haven't tried Stencil.js, might be worth giving it a go. I found it a dream for working with web components since it takes care of almost all the tooling, bundling, code-splitting, etc. out of the box, and has full support for Typescript, TSX and React-style props.