i've looked bit at trade and can't seem to understand it
what understand is:
the formule for trade is something like tradeports*(1+something*jumpinlongestroute)
uncolonizable planets dont count for longest route
you can see the longest traderoute by mousing over your credits

well now i have a few questions about this:
what do the vasari upgrades do? ads it another multiplier to the formula?
what does it do if i shoot those trade ships?
i think have seen some strange things in the longest trade routes if i have a lot of tradeports at one planet so does the amount of tradeports in you longest jump have anything to do with the formula?
what does a trade alliance do? another multiplier in the formula? and if i have a big trade network and the other a small one do i then want a trade alliance or is it the other way around or is it just a set amount of credits extra?

i would go and get the answers myself if i had time but i barely have time to play the game (
thanks in advance!