The point here isn't about showcasing skill, but rather about putting on a show and creating entertainment for the viewers. I don't understand why every game has to be about demonstrating skill. Heroes of Might and Magic is primarily about enjoyment, so why not create enjoyment for yourself and the viewers by playing a small map on a stream?
For optimal entertainment, some element of randomness is desirable. There's no need to turn it into chess, but the degree of imbalance introduced by this randomness shouldn't be too great; both players' positions should remain "viable."