There are two main types of maps in board games that I can think of, which I call grid maps and partitioned maps. A grid map has an array of spaces which can each only contain one character, whereas a partitioned map allows spaces to contain multiple characters. Gloomhaven has a grid map, specifically a hex grid, while Root has a partititioned map. In general, I think designers should favor partitioned maps over grid maps because it makes movement and interaction simpler, along with, by proxy, any automated mechanics.
Movement is simpler with partitioned maps since you never have to move around enemies, and characters “speed” values are smaller. In Gloomhaven, you must path around enemies and traps for most movement. This isn’t a problem in a game where players primarily controls a single character, but would be cumbersome in a game like Root. Speed values are also able to become smaller in partitioned maps, as maps tend to fit their contents into fewer spaces. Lower values almost always make games easier to reason about for players.
Interaction in partitioned maps also becomes simpler, since the “range” of interaction can default to 0—the same space. An ability that is able to affect a character in an adjacent space, or several spaces away, is the exception, not the rule. In grid maps, conversely, all abilities need to have at least 1 range by default, but often need to have a higher value, for the same reason that grid maps require a higher movement, resulting in even more counting of spaces during the game.
Together, the simplification of movement and interaction also makes automated mechanics simpler to administrate. Gloomhavens rules for enemy movement, though not terribly burdensome, are still more complicated than those in Final Girl. Say two enemies are supposed to attack a player, but it is possible for the first enemy that moves to choose a space blocking the second enemy. Does the player intentionally block the second enemy, even though an intelligent creature would not make that choice. Of course, there are ambiguities in the behavior of Final Girl antagonists, but not to the same degree as with grid movement and interaction.
Partitioned maps need not “maps”, as they are generally understood. In Arkam Horror the card game, the “map” is a set of location cards with adjecency icons. This fits, mechanically, with our definition of partitioned maps. There are a number of spaces that can house multiple characters and the characters are capable of moveing from a space to an adjacent space. Every game of Arkham Horror could have been played on an equivilant board, except the designers wanted to use cards instead.