I know, soccer is incredibly simple, however most Americans grow up on complicated Baseball and football, they expect soccer to be difficult and they completely over analyze the game. For example, corner kicks confuse the **** out of us, the ball goes out of play, so you kick it from all the way over there?
And play calling is different from tactics. In soccer you'll instruct your players to play a certain way, and your players know how to make runs at the right times etc... but it's usually not predetermined that player X goes to a certain spot as Player Y runs over there. The play calling can be quite complicated, with every man having a specific task that is meant to counter whatever the opposing players "may" do. They don't just get the ball and ad-lib with the general idea of moving the ball, they call a play and run the play as designed.
The 30 seconds rest isn't for the players btw, it's for the playcallers on the sidelines to get in substitutions and choose a play in order to exploit what they are seeing the other team do. Some teams, especially in collegiate football will actually play "Hurry up" which only uses less than 10 seconds in order to wear out the other team and prevent them from calling effective plays.
and yes Deon Sanders for a while played WR and DB as well as kick and punt returner, near the end of his career he only played DB and kick returner.