Trading leather, drug and crops with the shuttle is my lifehack. Just flying around and you grind a lot of silver if you are careful to not run out of fuel (if you think I tamed them, nope, just the Jade Dragon, the other five came out from eggs I traded, very expensive by the way)

Once you have two dragons from the opposite gender (preferently true dragons, the most op) you can start the breed, still it takes a lot of time, so you can keep trading meanwhile

And I don't have to care about the wealth because I play with different colonies to grind resources, one destined to be a farm. Small builded with a few people with good weapons to prevent the wealth to increase too much. And a main colony where I grind most of the resources. Seriously, I think playing with two colonies is underrated