This is why I love C. You can build these guard rails at exactly the right level for you. You can build them all the way up to CPython and do garbage collection and constant bounds checking. Or keep them at just raw pointer math. And everywhere in between. I like your approach. The downside being that there are probably 100,000+ bespoke implementations of similar guard rails where python users for example all get them for free.
It definitely is a lot of freedom.
But the lack of a good string library is by itself responsible for a very large number of production issues, as is the lack of foresight regarding de-referencing pointers that are no longer valid. Lack of guardrails seems to translate in 'do what you want' not necessarily 'build guard rails at the right level for you', most projects simply don't bother with guardrails at all.
Rust tries to address a lot of these issues, but it does so by tossing out a lot of the good stuff as well and introducing a whole pile of new issues and concepts that I'm not sure are an improvement over what was there before. This creates a take-it-or-leave it situation, and a barrier to entry. I would have loved to see that guard rails concept extended to the tooling in the form of compile time flags resulting in either compile time flagging of risky practices (there is some of this now, but I still think it is too little) and runtime errors for clear violations.
The temptation to 'start over' is always there, I think C with all of its warts and shortcomings is not the best language for a new programmer to start with if they want to do low level work. At the same time, I would - still, maybe that will change - hesitate to advocate for rust, it is a massive learning curve compared to the kind of appeal that C has for a novice. I'd probably recommend Go or Java over both C and rust if you're into imperative code and want to do low level work. For functional programming I'd recommend Erlang (if only because of the very long term view of the people that build it) or Clojure, though the latter seems to be on its retour.
I think the C standard should provide some good libraries, e.g. a string library. But in any case the problem with 100000+ bespoke implementations in C is not fixed by designing new programming languages and also adding them to the mix. Entropy is a bitch.