A really good start location has a river, preferably with several cattle around it. (Can you say "Settler Factory"?) I have come to dread flood plains in my start loc, you are taking a chance with disease. Once while starting as Russians on flood plains, I improved my floodplain tiles and started on settlers. You guessed it - as settler was almost done in size 3 Moscow, "Disease strikes Moscow". After the 3rd such message in 6 or 7 turns, I reached down and flipped the power switch on my PC. Take that, disease.