Settlers of Catan: which add-ons should I get?

[ShriekingDrake]

I've got the basic Settlers of Catan game, which turns out to be a lot of fun. With the holidays approaching, I was wondering which of the many add-ons to this game I should try to get. I'd welcome your suggestions and any rationale you'd care to share.

[Knaight]

Cities and Knights is easily the best. It and Seafarers are the big modifications, Traders and Barbarians is just a collection of little rules, to round out a collection. Cities and Knights introduces several new game play mechanics, some of which are pretty big, for a much more developed, involved, fun game. Seafarers adds ships and islands, which is fun, but really not that impressive. Get it only after Cities and Knights.

[fknm]

Cities and Knights actually turns Settlers of Catan into a half-decent game. Seafarers... doesn't.

I never played Traders and Barbarians.

[Vorpal word]

My friend says Traders and Barbarians is lame, but I never got a chance to play it (for that very reason), so don't quote me on that.

Cities & Knights is really good; I've never tried Seafarers but it sounds nice as well...

I don't know about the 5-6 player expansions. It sounds really good, but my playing group has always found that 3-player games are better than 4-player, so I don't know if the larger number of people will work out so well.

[BlackSheep]

I loved Settlers when I first encountered it, but once I played the Cities and Knights, I never wanted to play the base game again. It's that good.

I haven't played Seafarers tabletop, only on console versions. I did find that it added an interesting feature to the game by allowing and rewarding exploration. It doesn't add the depth that C&K does, though.

[Winterwind]

Yeah, Cities and Knights is the big one. The base game seems disappointingly simplistic and boring once one has played Cities and Knights. Seafarers is very, very minor in comparison to what Cities and Knights does.
No experience with Traders & Barbarians though.

[Shyftir]

I'm gonna disagree.

First, get the 5-6 player, because while yes 3 is more fun than 4 on the original map, that changes with the expanded map.

Play with the expanded for awhile. Are you still enjoying the game?

If your answer was yes:

Get Seafarers! Its not a huge change in game play but its a neat twist that doesn't require relearning the entire game.

Play with this a few times. Do you find the game too simple?

If your answer was yes:

Get Cities and Knights. Only play with others who are really into Settlers because, in all honesty, Cities and Knights is a much harder game to teach to new players due to all the changes. While some here are talking it up. I found it to obscure the simple beauty (read: hidden depths) of the original game.

[ShriekingDrake]

Thanks all for these excellent suggestions.

I like the idea of stretching out the joy. The only shame is that the game expansions seem to cost so much.