The truth is that size of government and economic freedom are inextricably connected. Any definition of "economic freedom" that doesn't directly incorporate the size of government is a crummy definition.
The essence of a free market isn't merely that people can buy and sell whatever they want on whatever terms they find mutually agreeable. Without the right to keep what you earn, freedom of contract is utterly hollow. A society that redistributes most of what you earn is economically unfree.
My point is not that redistribution, rather than regulation, is The Key to economic freedom. My point is that economic freedom has Two Keys. A solid measure of economic freedom wouldn't merely take points off for both redistribution and regulation. A solid measure of economic freedom would only classify countries as "economically free" if they had low redistribution and low regulation - and would classify countries as "economically unfree" if they had high redistribution or high regulation.