Naval combat is widely considered to be the heart of Aurora. But Aurora includes other elements as varied as industry, private shipping, and ground combat to enrich the simulation and provide additional strategic depth.
Because Aurora's sheer depth and breadth is enough to overwhelm any new player, I began by trying to acquire a deep understanding of the its economic elements before moving onto actual military design. Two principles rapidly became apparent: (1) economic growth is exponential, and (2) the size of an empire's economy acts as the key component of its military growth. For these purposes, I consider "the economy" to consist of four main areas: factory production, research capacity, mineral exploitation, and wealth creation.
Why is economic growth exponential? Construction factories create more construction factories (and mines, research labs, etc. ). At the same time, research labs are working to increase the effectiveness of existing factories and other installations. Mining and wealth act as constraints: as long as you've got enough money, and enough of the right kinds of minerals, to run the factories and research labs, everything is fine; if not, everything grinds to a halt.
How does the economy contribute to military power? Military power is created through industry, research, and mineral exploitation. Greater industrial capacity allows more numerous ships and ship components to be created more rapidly; greater research capacity allows them to be more powerful and effective. Again, mining and wealth are needed to keep factories and labs operational.
When these two principles are considered together, things get interesting. Economic growth may be exponential, but the magnitude of the exponent depends on the amount of economic capacity devoted to economic growth rather than military power. So economic growth and military growth are in a zero-sum game: to increase one, you must decrease the other.
Military growth may be non-linear - there's plenty of strategy devoted to seeking effective and cost-effective military action, after all - but it certainly doesn't seem to be exponential. So a potential strategy emerges: devote as much of the economy as possible to economic growth for as long as possible, then switch over to military growth only when needed. This strategy can be highly rewarding (see the example below), but it's also highly risky; if you miscalculate how much military protection you need, or wait too long to increase it, then the aliens are going to catch you with your pants down.
For example, suppose Empire A devotes its entire economy to economic growth, allowing it to grow its industrial capacity by 10% per year. From the same starting conditions, Empire B devotes half of its capacity to military growth and half to economic growth, so its economy grows at only 5% per year. In 25 years, Empire A's economy will be roughly three times the size of Empire B - so although it has no military yet, it can expand its military power three time faster than Empire B, allowing it to easily out-produce and out-research its competitor. However, if it waits too long to do so, then it risks premature hostile contact, which would reduce its highly developed economy (along with everything else) to a cloud of irradiated dust.
So how do know when the heavily armed xenophobic bug-eyed monsters are going to show up and make our day? There are three risk factors:
• Interstellar exploration. Moving through jump points to new systems risks the discovery or creation of NPRs.
• Existing NPRs. They do exploring of their own, and they might discover you. The risk is directly proportional to the number of existing NPRs that you choose during game creation, and inversely propotional to the size of the galaxy.
• Invaders. These are extremely aggressive, in the sense that they explore rapidly and are totally hostile.
Fortunately there's some element of player control to all of these: the first is the direct result of imperial decision-making, and the latter two are determined by the player in the meta-game. (Invaders can even be toggled after the game begins. )
Finally, I'll note that this strategy is totally defensible from a role-playing perspective. It's not hard to imagine a scenario in which the Trans-Newtonian Revolution cures all social ills, rendering war obsolete. (In fact, the total lack of intra-imperial income disparity seems to support at least some of this. ) Then the newly de-militarized society begins optimistically growing and spreading. When it makes first contact and somebody gets blown up, everyone else buckles down and starts making bigger laser cannons. (For an example in literature, see Larry Niven's "The Warriors". )