Ada makes a real effort toward if it compiles it works, which is an exaggeration of course but Ada is much closer to that ideal than is C. More recently we have Rust, but Ada is too often overlooked.
I'm not quite sure what to make of those criteria. If you want a platform for writing DSLs, I believe Racket Lisp is impressively flexible, but it's a somewhat exotic language.
For flexibility and conciseness, functional languages are the obvious place to look.