The chart below shows the advantage of being on the play or draw across different formats, along with the average game duration. In general, we expect shorter games to yield more of an advantage of being on the play, as the extra card from being on the draw doesn't have as much time to be worth it. We also expect the hand smoother used in Bo1 to give an advantage to being on the play.
Note that this includes data for both the person using 17Lands and their opponent, weighted by the number of games in each situation. It also only includes data from game 1 in best-of-3 matches. Because of these we do not expect win rates to be biased by the higher-than-average win rate of 17Lands players nor high win-rate players being on the draw more in games 2 and 3 of best-of-3 matches.