I could go through all the reasons why best of three with the time limit is awful for the game, or how it discourages newer players from starting out in large tournaments, or how ties are an unbelievably stupid system. But in the end, all it really comes down to is that it makes the game less fun. Bo3 is inherently better than single game, but not if there simply isn't enough time to accommodate it. I hate nothing more to be rushed in a turn-based game, or feel disappointed as my 6-1 prize lead ends in a tie because I didn't get one more turn. The problems with best of one right now are largely alleviated due to the first turn rule, so please, PLEASE let them go back to that.
Also, before someone makes the comment "you simply need to play faster" or "good players will find a way to succeed," don't. Good players will always find a way to succeed, and being forced to play faster is the problem in the first place. And even with faster play, ties are still inevitable.