We've always played 6-game matches in the Dominion League. I don't know all of the reasons for this precedent, but I'd like to at least consider transitioning to 4-game matches (not this season, of course). I believe that circumstances have changed recently in two relevant ways:
Games last longerEmpirically, this is the case. I'm a slow player, but on the Making Fun platform, I never had a 6-game match last longer than 2 hours. On the ShuffleIt platform, almost every Dominion League match has lasted over 2 hours. My experiences are not unique; others have reported that recent matches have been lasting longer than they used to. The new platform (and getting familiar with it) might be responsible for some of the game duration increase, but I believe that the following reasons are more important:
- The addition of Adventures, and - especially - Empires. Adventures and Empires both introduce cards with a lot of decision points. They also introduce Events and Landmarks, which add additional nuance to the games they appear in. Most importantly (IMO), Empires adds a lot of different ways to get VP. Games with alternate VP tend to last longer, and Empires has so many alternate ways to get VP (including all of the landmarks). I find it increasingly rare that buying only Provinces (and some Duchies) is the correct strategy in a random kingdom.
- The removal of 1st edition duds. 12 dud cards have been removed and replaced with reasonable cards that might be purchased. This makes it more likely that any given kingdom has all of the components necessary for an engine. Monolithic strategies are less effective than they've ever been for this reason (and the Empires Alt VP).
While these two factors make an average game of Dominion more interesting, they also make it take longer.
Games have less varianceThe same factors that result in games taking longer also provide more opportunities for a skilled player to tilt the game in their favor, or even bring it under their control. While there are still some kingdoms with obvious strategies - where victory hinges mightily on shuffle luck, there are many more kingdoms with so many decision points where skilled players can reasonably disagree about the best approach.
For these two reasons, I believe many people would look more favorably towards 4-game matches. I think that 4-game matches in the current climate will take about as much time as 6-game matches in the past, and offer sufficient opportunity for a more skilled player to turn the match in their favor.