I understand JS was an experiment and that there was much to add to make it a proper language, but isn't it good enough now? Can we expect the pace of changes to slow down (specially in light of WebAssembly)? I'm not a JS developer and/or language developer, honestly just curious.

JS still lacks support for 64-bit integers and BigDecimal support would be extremely nice. Otherwise I think the language is good enough.

Just in case anyone is not aware there is a stage 3 proposal [1] for 64 bit integers right now called BigInt [2].

[1]: https://github.com/tc39/proposals

[2]: https://github.com/tc39/proposal-bigint