I've been thinking of writing a language with Rust's ergonomics but less of the memory safety stuff. I prefer using no dynamic allocations, in which case the only memory safety feature I need is leaking references to locals into outer scopes. As for the thread safety stuff, most of my stuff is single-threaded.
The code I have in C is often code that does't fit in Rusts safety model. Dealing with ffi is annoying because slices have no defined layout. `dyn` is limited compared to what I can do with a manual vtable. I have seriously attempted porting my personal stuff to Rust, but theres enough papercuts that I go back to C. I want the parts of Rust I find to be helpful without those parts I don't.
To add to the sibling comments, a world-class LSP enabling you to get a great experience in any editor/IDE out of the box. This is not at all exclusive to Rust of course, most strongly typed languages have one at this point, but I've been working in Python lately and this is what I miss the most. (I'm using an LSP in Python, but it isn't as good at the best of times, and it seems like no matter how many times I fix it's configuration it's broken again the next day.)
I love how everything is an expression with a value. And match expressions are quite nice, especially with the option type. I really miss those when working in javascript.