In a paceline it's easier to watch the guy in front of you's lower back than try to stay two inches off his rear tire by fixating on his wheel. At least that way your head is up and 'should be situationally aware. The guys to follow in big group rides are the tandems, if there are any; they hate drafting off most singles and are about as steady as it gets, speed-wise. Generally less squirrelly, too.