Take a look at Zig (ziglang.org). Not sure it meets all of your requirements, but looks like it might. I haven't worked with it yet, but it's on my radar, as is FORTH, for the simplicity aspect you mention. And I should mention Tcl, but that's a scripting language so not what you asked for, but just in case, no, Tcl isn't 'dead', it's in most of the Cisco and other IT infrastructure equipment that's getting this website to you, it runs most of Flightaware's infrastructure, and is in all sorts of places quietly doing its job; it's how SQLite was started (as a Tcl extension, and Tcl is still a first class citizen w/r to SQLite). The creator of Redis wrote a good article on Tcl (which Redis was started in). Oops. This became a Tcl sales comment. Sorry! :)

http://antirez.com/articoli/tclmisunderstood.html