True, Nagato has a f***ed up past, but how many times have we seen the 'avenge parents/friend' angle. Not saying its bad, just so very common.
I thought his angle was "peace." When everyone understands the pain of war, fully, they won't go to war anymore. He wasn't really on a revenge mission on Konoha, he was on a 9-tails mission. I think he was just trying to make a point with Naruto about the whole revenge thing.