Muon, I agree wholeheartedly. When I say I support "populär vote" elections, I merely mean that the President should be directly elected by the people, and not by an electoral college.
IRV would be the best possible system.
My statement underlies my great objection to the NPVIC. In order to get around a constitutional amendment, the Compact cannot use any kind of runoff to select electors. Nor can it use an IRV in the states with a Compact, since it wouldn't be known in the other states which candidates would be left for a runoff.
The hope is that the NPVIC would ultimately spur the adoption of a constitutional amendment relating to Presidential elections.
Only if we a had a strong three-way race that ended up with a winner who got less than 40% of the PV and that the supporters of the other two candidates both opposed, so that it would be obvious that if a runoff had occurred, the winner would been strongly trounced.