Rather than straddle the middle, I think I'd go with as high-level a language as I could get, coupled with a simple low-enough-level language to get whatever pe

Rather than straddle the middle, I think I'd go with as high-level a language as I could get, coupled with a simple low-enough-level language to get whatever performance benefits I needed. Some combo like Python/C, Clojure/Java, or maybe some other lisp dialect and C.