But be careful because if you only bid for one thing and it is something very popular! and you end up not getting it; because the computer can't see any other preferences, you could end up with lots of things that you wouldn't want.
I always put a few very low points generic choices at the bottom of my bid, so that if I have been unsuccessful with my main preferences, there are at least a few things that the computer can see that I wouldn't mind, i.e. 50 points any three day 2 sector trips and 10 points for any 3 day 2-8 sector trips, as a kind of an insurance policy!
My advice would be to make sure there is a large gap between your most wanted trips with a bid of 200 each, and then some second choices, of say 50 or even just 10 points. Also if you want a variety of different destinations, make sure you put 1 in the frequency box. So for example you could put in three or four trips, asking for each just once and give them all 200 points. Then make sure that you bid for your days off in groups of two, spread evenly across the month. That way you wont end up doing a tiring group of trips with just one day off after it.
If you bid for things in a way that makes it easier for the computer to roster you, then your bids will be more successful.
The trouble is that we all bid differently and you could ask ten different people how to bid and they will all say different things. Some crew put in very simple bids with just generic choices of trip length and sectors and some put in very detailed bids that are pages long. It is just up to you to try out different ways and see what is successful for you.
Hope that helps some of you.