We only watch one side of the field (red). With each team playing 12 times, we get 5-7 views of each team which is enough to make an informed opinion - plus we can get by with only 3 scouts.
Here is the sheet we've been using this year. We just log each match - draw the robot path on the right, graph the stacks and times on the left, and make any other notes on the top. It worked pretty well our first event, and we'll be using it with another team at INKOK.