Initial settlement placement in Catan can really affect the outcome of the game. What strategy do you follow in Settlers of Catan for initial settlement placement. Does this strategy change if you have first, or last placement? Also, when playing Seafarers, do you alter your placement strategy?
If I'm the first player, I always go for the most powerful settlement, since I have no idea what I'll get when it comes back around to me.
If I'm last, I grab spots that based on the numbers and the available ports will get me an advantage. I also like to try to place the second settlement on a brick/wood combo so I can start with a road.
The other positions are variations in between the others.
In general, I try very hard for number diversity. I love it when I can get both a 6 and an 8 placement. Next in line is at least 3 of the following: 5, 6, 8, 9.
The final thing you have to look out for is that you have somewhere to go.
There are a ton of variables to deal with, such as where everyone else has already placed, the numbers on the resources, and nearby ports.
I always like to try and get my brick/wood combo on my first placement, because that's absolutely necessary for roads and settlements. For my second placement, I'll go for whatever I'm lacking. If you have to skip out on a resource, I generally skip out on ore, because you don't need it until late game.
There are always exceptions -- I'm a sucker for a high-number resource with a matching port nearby. I'm also a sucker for placing two settlements so I can get both numbers -- yesterday I managed to get lumber and brick on 6's -- instant roads for every six.
I haven't played Seafarers, can't help you there.
I try to maximize the number of numbers I have. This works especially well when playing with the lake tile from Traders and Barbarians.
In the last game I played, I was eventually able to get something (unless being robbed or a seven is rolled) with each roll and won because of it.