TIP 1: try to colonize the farther planet first and then the close ones... (everybody knows that right?) |
Well, that suppose you have the time to reach farther planets before the AI grab those close to you 
TIP 2: don't spend money on trade ships and trade, in the end you only get from it 12 bc, but you spend 990 bc only on on trade ship... |
Are you really sure? 12 Bc is generally what I get from the trade route when the minifreighter is near my planet (I play on large galaxy). But the trade route generates an income each turn that increases when the mini-freighter steadly until the mini-freighter reach the alien world. You can see it when looking on the trade tab in the economic screen (the one where you set sliders).
Not to mention that trade ship is useful to increase slowly your relations with others races. And sometimes, you might want to rushbuy trade ship in order to have your trade network established and allow you to concentrate on other thing.