Would sure make Presidential Campaigns cheaper and easier.
Not sure about the Constitutionality of doing it via ballot initiative, though I think the Constitution is pretty silent about appointing electors.
I agree about that. The US Constitution is very explicit about the state legislatures having the authority to determine how electors are chosen.
From Article II, Section I, of the US Constitution:
“Each state shall appoint, in such manner as the Legislature thereof may direct, a number of electors, equal to the whole number of Senators and Representatives to which the State may be entitled in the Congress...”