Although instant run-off and other ranked or "preferential" voting models are an improvement over plurality, we should be advocating for better and simpler models such as approval voting or score voting. Approval and score voting are cardinal methods that do not require that the voter order their preferences. Preferential models such as IRV require a strict preference order be specified by the voter and are much more complicated.

My go-to resource for voting reform is the Center for Election Science [1].

Perhaps the worst feature of IRV is that it's non-monotonic, meaning that in some cases, voting your sincere preference can actually hurt your preferred candidate. See the linked part of the video in [2].

[1] https://www.electionscience.org/

[2] https://www.youtube.com/watch?v=2q_eMUGCU5U&feature=youtu.be...