ORIGINAL: zgrssd
Isn't that alrady in DW1?
No planets will produce every Luxury and Strategic Resource it needs for growth. But there is sure to be a planet or mining station that does. If it is a planet, you get interplanetary trade. And planets should be prefered, given that you might be able to transport something in both directions.
Maybe they could add some inherent tourism between planets? IIRC tourism in 1 was only towards places with bonus scenery (and propably a resort base), but there should be some tourism attraction for every planet. Especially if it is a different clime and as high quality/development.
Yes... the difference would then be that those goods have different uses and abilities and you ONLY find them no populated and industrialised planets you can't find them and mine them anywhere else. These resources still are part of planets development and should be able to change over time depending on the supply and demand of it's surrounding. A planet that are developing should be more likely to provide a good that there is a high demand of as that would earn the planet more income and a slightly higher development which means more goods produces.
Already developed worlds could change the good or the amount they produce but the more developed the world the slower the change should be. This would mean a world that once produced a very sought of good might later produce something that is not so hot anymore and as the world have a high development it is slow to change. Small developing colonies will change their production of goods much more rapidly as they are still able to change more quickly.
I would like such a system where large developed planets are more stagnant than small new developing colonies. It also would encourage more "trade" between planets without a complicated resource production system in place. It also wouldn't burden the player in other ways than providing the infrastructure and making sure you get trade agreement with other powers that have the goods that you want or can sell.