It’s easy to underplay the “board” part of a board game as merely serving as the boundaries of a game rather than as a fundamental part of a game's design.
Ah, the joy of a physical tabletop game. I could probably tell you the quality of a game based on the sound it makes when shaking the box. Many tabletop game reviewers devote sections of their reviews to discussing tangible components of play and for good reason. The physicality of board games is crucial to upholding a thematic play experience. Compare the feeling of a weighty copper coin versus, say, the flimsy paper money that plagues Monopoly. The thickness of cardboard can make all the difference when measuring the care a designer puts into their game. The physicality of material is crucial, but above and beyond quality in terms of importance to enjoying a game is the use of physical components in complimenting and defining the aesthetics of play.
Despite the fact that all board games have physical components by definition, it’s easy to forget how minute decisions about physical designs improve play. Take The Great Fire of London 1666 for example. Designed by Richard Denning, the game simulates the titular conflagration that razed huge swathes of London in the 17th century, destroying some 13,000 homes. Setting aside the cone-shaped wooden fire markers (delightfully solid by the way), the map design by artist Andreas Resch is gorgeous and instrumental to the aesthetic of Great Fire. Yes, the board itself is drawn as though it’s an old-timey wood print, lovingly reflecting the time period depicted in the game, but more importantly, the game’s spaces are tiny.