Your initial list pretty much exactly describes Pyret. It doesn't have JS's warts, but still runs in the browser entirely. It's higher-level than C and C++. It

Your initial list pretty much exactly describes Pyret. It doesn't have JS's warts, but still runs in the browser entirely. It's higher-level than C and C++. It doesn't require types or a JVM. It isn't like Perl in any of the zany ways. It's a bit like Python and with totally sane scoping. And it's very much like Scheme but with conventional (infix) syntax and lists, sets, maps… And it's used in several high schools already.