The trade aspect was discussed several times.
Since the modules are only active when the mini frighters are in the same sector as the starbase it is not easy to use the trade boost.
Since the mini frighters do not use the same path on the way back when the two planets are not on the same horizontal or vertical line of sectors (i.e. in the same column or line) and the amount of starbases is limited through the logistic costs I know only of two main trade starbase tactics.
1. Trade with another nearby planet on the same line of column and build one or two starbases in each sector. With this method you can get very high trade income early on.
2. During the endgame when terror stars are available you can use my "Trade Terror Star". More details can be found here: http://www.galciv.com/forum.asp?BID=GS&id=123185#203399
The Trade Terror Star is especially heplfull when you establish several trade routes at the same time.
e.g. you lost several routes due to a war with your former trade partner.
When I'm ready to conquer the galaxy I park enough frighters nearby a minor, or a race I put aside to the second wave, and enough constructures at my homeworld to switch all trade routes at once. That's more thean enough money to fund all your warships
Yes I know that you don't need to do that since you already won at that point of the game but it's still fun LOL LOL LOL
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