Rule coherency is more important as the rules become more complex. “Monopoly” is a simple game: Roll dice for movement, and where you land has a limited set of results (buy property, pay rent, draw card). Because of this simplicity, these rules’ interactions do not need to be “internally consistent”; they can be arbitrary, yet they also do not conflict. There are no meta-rules needed. Dice rolling does not interfere with rent, etc. However, if you were to evolve more rules, or add new branches, these would either need to be organic and consistent, or would require meta-rules to resolve conflicts.