I'd love to do something useful with the PoW result but like you say, the PoW should be able to work in browsers, so they are intentionally small. The maximum

I'd love to do something useful with the PoW result but like you say, the PoW should be able to work in browsers, so they are intentionally small. The maximum advisable delay is ~10s but even then it might not be enough for it to be useful.