1. I'm not familiar with the hardened stdlib stuff except for the msvc debug runtime but if you have a solution for this, skip this one. You presumably want boundschecking (and throwing/failing hard) or at the very least, logging out of bounds accesses.

2. A non-inlined grow. If you have large collections you modify often, you want a vector implementation where the reallocation is out of line and the rare case. All the STLs treat it as a normal method and have inlined by codegen.

3. Trivial relocation support so you don't need to destruct objects where there are no pointers inside or external objects pointing to them.

In your case it's probably not as relevant/important, yes