Rust 2018 - Growing in elegance and responsibility
First; I have the utmost respect for the fact that I'm mostly sitting here wishing, while other people do the actual work. But since you asked...
I tend to think of Rust as a language in its teens. We're no longer that child which breaks people's code every other week (like before 1.0), but the language has not really stabilized either. We have many heavy things in flight: GAT, impl Trait, specialisation, NLL, procedural macros, and so on.
And part of growing is learning to say "no". Saying "no" is difficult, because a lot of people might have worked with thinking and evaluating an RFC, believing in it. It's easy to go for the easiest solution that solves a specific problem, without thoroughly consider if there is a more elegant solution that solves a whole class of problems. Even tougher is saying "no" and offering no solution at all (because there is no s