Still a hard no from me on switching to IRV.
I agree with the idea of just codifying a rule for mistakenly ranked ballots. It’s a way easier fix than completely switching voting systems (especially when there’s good reasons for why we use AV for Delegate, but I won’t bore everyone here with that again ). However, as Welly already wrote, I think it would make more sense to consider all candidates ranked above RON to be approved, instead of only the first choice:
On their AV ballot, the voter tells us all candidates they would support over RON. In case they mistakenly rank the candidates, the resulting list also declares which candidates they support over RON. So in both cases, the voter themselves, without any subjective re-interpretation necessary, provides us the exact same information. Plus, this would always produce the same list of approvals, whether a voter properly used an AV ballot or mistakenly ranked the candidates (assuming honest voting), so I also don’t believe that voter agency would be subverted with this.