Tbh, I don't think you're the first person to think that but the trouble with making a "safer C" is that it's not C. Or to be more precise, it looks like C but isn't C compatible. This has ended up killing most attempts. Apparently nobody actually wants an almost-C language (alternatively, nobody has yet managed to successfully market one).

There seems to be an uncanny valley effect with C-like languages. The best you can do is have non-standard compiler extensions on top of ISO C.