The justification for keeping the College is the same as that for keeping the Senate having two senators per state, rather than proportional representation as in the House. It keeps the densly populated parts of the country from running things to suit themselves.

Lazarus Long (Robert A. Heinlein) said:

Animals can be driven crazy by placing too many in too small a pen. Homo sapiens is the only animal that voluntarily does this to himself.

The incidence of craziness is vastly greater in urban areas than in rural areas. (But not of stupidity - that's evenly distributed on a percentage basis.) It follows that the country should be run by the rural areas. Strict adherence to One-person-one-vote would cause it to be run wholly by the urban areas (at least until the urban areas, making rules for how agriculture should work while knowing nothing about it, created a system that made it impossible to farm, and everyone starved but the urban areas starved first because they were farthest from the food and needed the most, but I digress).

Peter.