Out of the things you mentioned and what you are looking for, the question might be simplified with technologies currently that will have legs. My opinion is Go

Out of the things you mentioned and what you are looking for, the question might be simplified with technologies currently that will have legs. My opinion is Go, and my reasoning is it's probably going to be the same as if you started with C# back in the day when it was introduced. There is a large company behind it that is investing it the tech and stack, just like Microsoft isn't going to stop with C# anytime soon, I'd imagine Google is with Go on the long haul. I'm interested to hear opinions about this, since this is what I have chosen and reasoning behind it. The other one is Javascript, just like PHP it's ubiquitous enough that it will offer opportunities on the long term, though they both have less high paying opportunities because there is a lot of supply to match the equally high demand.