It would be great if you could file these as bugs against esbuild! Sounds like these should be easy to fix.
One thing to be aware of is that some other tools that integrate esbuild do so incorrectly. For example, the 3rd-party integration of esbuild into Webpack mis-configures esbuild in a way that causes issues with JSX: https://github.com/privatenumber/esbuild-loader/pull/107. This isn’t a problem with esbuild itself.