I wish #Haskell had as well thought out an edition system as #Rust. https://github.com/rust-lang/rfcs/blob/master/text/2052-epochs.md

I think it would handle things like replacing `*` with `Type` quite nicely, for example. There would still be the question of the scope of the standard library, for which I’m unaware of an approach that makes everyone happy all the time, but keeping old code cleanly usable is so, so important, particularly for smaller communities!