To me, it isn't really dependent of the map unless the map is very extreme in size (large or small). Instead, I tend to focus on what the current style of game play is based on my enemies' team. Additionally, I take into account what type of class I am playing which varies time to time. Usually I play Assault, but hitting up the others can fun when either available or when I feel like it.
To better explain understanding the type of strategy being used by my enemies, I think about how they are playing and try to change my style of game play to best benefit my teammates. Now that I think about it, I also try to assess how my teammates are approaching the current match. On most of our maps, we need to have some people stay back a little to protect the enemy from flanking the rear. Simultaneously, we need people to attack to attempt to gain ground. Basically, I take my strategy according to what is set before me and adjust accordingly to win the match. Unfortunately it doesn't always succeed.