Just a note: This is an alpha release. However any clojure code should also run on the original Clojure implementation which runs on top of the JVM.

I love Clojure!

What I wonder is whether the sheer complexity of C++ is a good base.

There are Scheme implementations like Guile which have good interop with C, and which also compile to native code. And there is Steel, a Scheme written in Rust. Scheme is similar to Clojure in that it prefers re-definition over mutation of objects - but it is less opiniated, and one could argue that it is more practical. (Though Clojure as a modern Lisp is quite successful in some applications.)

Oh, and I don't mean to pick on Common Lisp. Common Lisp is seriously underhyped. Apart from its stunning elegance, the concurrency support based on persistent data structures as default types is where Clojure has great innovations.