Right, that is much more important than performance, as I said as well. But I think that whether your Python will age well or your Go depends more on the team

Right, that is much more important than performance, as I said as well. But I think that whether your Python will age well or your Go depends more on the team and their level of experience with either tool. Use something reasonable, and pretty familiar, and stick to it. Don’t do dumb stuff like going crazy with metaprogramming, and avoid excessive abstraction - but those are just always the required conditions for keeping your group functioning well. Any language can be abused; abstraction is not really a property of a programming language choice.