Multiple teams is already cheating - this way you´re only to get caught easier. So this is not opening another door for cheating (as those who may use it by your way are already doing it anways), it also opens up a way of catching them.
I do see your point in lowest leagues of a country to some degree, but those leagues are filled with bots racking up the high picks anyways, so after all there´s a solid risk of straightout losing your money after you bough the 13th pick because some of the bots before you might accidentally grab one of the three useful players in the draft nowadays.
Opening up draft picks for the whole market doesn´t make much sense to me, as you simply have no scouting information about a foreign league. I prefer the closed market solution because it really adds another variation to the drafting process - it´s not even guaranteed you find a buyer for your pick. And writing down the price of your choice, only to make it a "will someone buy or not" thing seems pretty reasonable to me
You can make a ladder system, like:
no. 1 - 1,000,000
no. 2 - 900,000
no. 3 - 800,000
and then
no. 4 - 750,000
no. 5 - 700,000
...
no. 16 - 150,000
and no 2nd or 3rd rounders available for trading at all - the prizes sound pretty reasonable to me, and still leave enough "fantasy" in the market so that pondering whether to buy or sell is no easy choice.
Zwei Dinge sind unendlich, die Dummheit und das All...