The initial cards are equal in value, they are just random. Each is worth 30 points when fulfilled (the total of the delivery points and the card points).
I'm sure that isn't right. There's a (really fiddly) calculation you need to do at the start when you are given your starting order whereby you calculate its actual value based on the value of each of the different types of produce at the villages requesting them. From that point you can decide whether or not it is worth completing the order as a matter of priority or not.
In our last game I had a starting order worth 25 points (the maximum it can be worth) and the other player had a starting order worth 11 points only.
If the dice rolls have been really against you it isn't beyond possibility (although it is unlikely) that your starting order is worth less than 5 points, or even zero points!