Pros:

You know how we constantly have to pick the "lesser of two evils" because of our two-party system? A two-party system is only guaranteed in a first-past-the-post voting system.

Ranked choice voting gives (typically) three choices and you rank them in order of preference. If, after the first tabulation, a candidate does not have a majority of first-preference votes, then the candidate with the least votes is eliminated. If the eliminated candidate was one of your choices, your vote transfers to your other choices. This cycle of tabulation, elimination, and transference continues until a candidate has a majority. This system would allow third parties to exist and be electorally competitive, as people will be able to vote for them without "wasting their votes."

Cons:

Honestly, it takes longer and could potentially be confusing.