How to do ranked voting for the President

I just had an idea as I am on the bus listening to Hamilton about how we could do the Presidential election using ranked voting.

The President is very obvious, we vote for the President and rank them by number using IRV. This is the most fair system since having more than 2 parties is far more likely than an election between two candidates which is within a 5% margin.

The Vice President is another question. We could do two different ways, either every Presidential candidate names who they will have as VP or we could do it with ranked voting from the Presidential race. We would calculate the winner for the Presidential race and then for the VP race eliminate the President, allocating their votes as if they were the lowest ranked candidate and run a normal instant runoff voting election. This would be similar to the original system where the vice  president was the runner up but also ensure it is someone the majority of Americans can agree on.