It actually much tougher to create a "fair" bot than one that is optimized to win. With the number of different battle modifications, size of hand, splinters its pretty diverse and there won't be statistically significant line up that you could put together to make it even.
As an observation, when calculating odds of winning a lot of the simulators will calculate results of 0 percent or 100 percent. You will rarely get a 50% result which is fair.
Also "fair" matchup requires knowledge of the opponent. You can do this based their % win rate for the last 50 battles which in my opinion is not statistically significant or their actual team submitted which has different problems.