There's definitely already a lot to learn with Malifaux, so it could become a blocker for casual/new players: BUT, when playing at a local gaming club, there will likely be a limited number of master's you'll see, so until you go to tournaments you won't have to learn every master to be competitive.
But, tournament organiser could make you pick masters for each round up front and then a week before the event let you know what the ladder looks like. It would stop counter picking, but would be beginner friendly. Not really sure if that's a solution or another problem...