Trading

1) farther

2) high pop planets (both sides)

2) high income helps too.


enjoy

I am currently maintaining 6 routes from my 3 best planets to the Iconian 3 best planets on the other side of the galaxy. The most worthless route is worth 47, the most expensive is 56. Large galaxy. It pays to scout out your trade routs beforehand. And to strategically place starbases around everything. There isn't a single pixel in my homezone(the area where I started, and made the first landgrab, roughly 3 sectors) that isn't covered by a military starbase, and not a single planet is without an economy starbase. Starbases save lives.

Most important factor is distance - if you track the value of the trade route as it moves along the route, you'll see it periodically jumps on long routes. How often depends on the size of map. Oh, and it's distance rather than the turn time it takes to travel the route, so try and make the routes diagonal (40% longer for the same "time distance" than straight routes)

Population's a factor...it depends on the sum of populations on the two planets. But this is a much lesser effect than the distance bonus (which seems to be independent of population) so just set up the longest diagonal routes you can as priority. If there happen to be high population planets in the vicinity, then great, but otherwise don't worry about it.

2) high income helps too.

Are you sure? Try changing your income by changing your tax rate. Unless they've altered things in the current beta it won't have any impact on the trade route value.

Unless you're on smaller maps, I wouldn't spend too much time on trade. Also if you're building eco starbases, range may not be as important. (longer the route, the less often it's in the bonus area of any one of your starbases.)

Remember building the freighters takes time, money, and you lose building a warship. Remember building eco-bases takes lots of constructors and money as well. It's a lot of resources to dump for the gain you get. On the smaller maps it can sort of work out for money.

For me I don't even bother with it anymore since i play gigantic and the best you can get is ~2k/week. (maybe more, but no-where near you're 50 to 100k from tax revenues.)

I generally don't need improved diplomatic relations, but that is probably the only good reason to bother with trade on larger maps.

Remember building the freighters takes time, money, and you lose building a warship.

And don't forget the time it takes to get to the target, as well as protecting it.
You're better off building a few stock markets.

In the larger galaxies, I try to identify a high-class planet (17+, with 26 being ideal and I'll consider Class 15 or 16 worlds if they have enough farm and/or morale bonus tiles). This will become my paradise planet. On it I build the Restaurant of Eternity and my Economic and Political Capitals. I try to have at least four factories and a starport, along with ten farms and enough stock markets and approval buildings to keep morale at or above 75%.

Why does that paragraph belong here? Because I build all of my freighters on this planet. When possible, I identify one trade target - the capital planet of either an AI faction or a minor faction, if I think that minor will survive the game - as far from there as possible and send my freighters there, trying to space them out evenly; one every ten turns or so.

I build tons of econ starbases along that one trade route and max out their trade modules. And then of course pray that I will be able to defend tht extended route and that my trade partner will stay in business throughout the game. With this setup, you can lower your taxes way down to keep up approval on your high (25+) population planets and still stay in the green.

It's a lot of work to build and maintain, and I don't recommend it if you are planning all-out conquest sooner rather than later.