It is better to do tournaments because adding more and more ladders is expensive on our server. We already have 3 ladders which we believe represent the majority of the playerbase. There will always be more formats but we can’t add a ranked ladder for each of them. Adding more queues also divides the playerbase which means less players are on the queue which will ultimately affect the matchmaking too since there’s a higher likelihood of getting matches against someone who might be much stronger or weaker.
It’s best to host Speed Duel tournaments using the Speed Duel banlist.