I've been trying to think of this from an alternative perspective. I've had weeks that it looks like, "What's the point" and I have had weeks that are pretty good opportunities.
I originally thought, as many have voiced, that it should be fair across the board. Everyone should have the same valued assignments. However, if everyone had the same valued assignments the final score would be a whole list of all the same score because everyone would only do the highest assignments, but if you tie assignments into something else that guarantees a variety then you have a wide ranging variety of scores. I get that, but people want a contest not a randomized luck fest.
I've tried to make sense of exactly how things are being done. I had a theory for a while that the next assignment may be tied to the assignment you just did. Previously I chose mostly mid-range assignments 800-1500 and always got mid ranged assignments in return. This week I was just going to play around with it and do a variety of all different assignments including low valued assignments and see what I get in return.
I thought I was onto something when the first assignment I did was only worth 320 and the next assignment I got was worth 5000. I did the 5000 and then got a 2000. I do the 2000 then got 800, so decided to mix it up again. I did a 580 assignment and got an 1400 in return. I did a 400 assignment and got a 380 in return. I do a 1080 and get a 1420 in return.
There does not appear to be any rhyme or reason to it. Although the complete random way I went about doing this week's contest does have me currently in first with 4 assignments and 2 days to go and the average across the 16 assignments I've already done is just over 2000 per assignment.
Make of it what you will, but I will continue doing the contests even during the weeks that I have no chance if it will gain me one extra gold key that I would have never gotten otherwise. Those are just the weeks that I will not concentrate as hard on it, but do the bare minimum to get a gold key.
The only thing I really have to gripe about this contest now is that I really wish they didn't add a 4th currency item. Platinum keys? Really? Sure add more things you can put in your city and give keys as rewards, I'm all for that, but I really don't think we needed a 4th currency. Simoleans, SimCash, Gold Keys and now Platinum keys. UGH! I would have preferred just an increasing number of a gold keys and have all the newer buildings cost more.