There used to be a place just past the UK pavilion, before the bridge to France, where there was seating right down by the lagoon and it always seemed few people knew it was there. I don't know if this has been taken over for VIPs, special groups, etc.
Last trip we were able to find last minute, up front spaces between Germany and the African Outpost. Someone here mentioned that the crowd (except for the busiest days) tends to thin out as you get over there.