Don't try to fix everything at once
They have a limited amount of time to create a new set. They have about half a year to playtest the cards before finishing it. They playtest about one or two times per week during development. The most important time is during the beginning, because your first concern is to fix the cards and the set before going on to finish it. From Sam's personal experience he says that there was often an urge to finish the set as soon as possible. There is the problem, you can't rush things. There is always room to improve. One measure that he has had a hard time figuring is the right number of changes from playtest to playtest. Too many changes and you get lost because then it becomes hard to track what changes are working and which ones aren't. You gotta keep the number low to avoid losing track of your process to improve.
I can see that the same thing happens with level design. Trying to fix too many things at once is not going to work. By extension, the same applies to game design as well. We often want to finish the job by burdening ourselves with all problems at once. We have to practice patience here and this applies to life itself. Now comes the question: Which problems to solve first? How many of them first? My answer would be: try to see which of them are core issues and which ones are easier or faster to solve. We certainly have a complex web of interconnected problems, but there is one skill that everyone should have at some degree that is to try to decompose things into smaller pieces. One of the most valuable lessons of college is that any type of problem, no matter how complex or big, can be tackled from multiple viewpoints. Mark Rosewater himself likes to see magic from an holistic viewpoint. Try that, try to see a problem from different perspectives and try to see how smaller problems compound into larger ones.
I can say that I've had the same experience as Sam. You make a level and then want to finish it as soon as possible. You desperately want it to shine and you don't want to waste too much time polishing it. The problem here is that if you forget the initial plan or don't follow a schedule, you are most likely going to waste more time remaking things, restarting things, making last minute changes, over and over. We have to reach a point where enough is enough and the process to reach it is more important than being obsessed with perfection, which is what Sam is saying.
