personally i'd like to see something like this
I would like to see a space colonization game work something like this:
You start with Earth in a fictional 1990s. For all intents and purposes, we'll boil down the initial game to a starting six factions on Earth: the United American States, the Soviet Union, Mittleeuropa, Eastasia, and Panafrica. Each faction has its own culture, different tech positions, wealth, political system (ex. UAS = Democracy, Soviet Union = Proletarian Dictatorship, Mittleeuropa = Constitutional Monarchy, Eastasia = Absolute Monarchy, etc.)
The game would begin with all nations trying to advance down their tech lines. Tech could be divided into the categories of Economics, Astrophysics, Biology, Military, and Infrastructure. Economics would allow increased development of resources (and therefore more income), Astrophysics would allow for better ships and propulsion, Biology would allow for higher population growth and terraforming, Military allows for better weapon and defense systems, and Infrastructure would allow for superior structures and construction on different types of worlds.
Initially all nations have what are essentially guarantees on each other, making a war against any other faction virtually suicidal. Instead, nations will likely try and advance in space as much as possible. The star systems around Earth will be randomly generated, and what Infrastructure allows you to do is build superior space telescopes and such to have more "vision" of worlds. Once a world is detected, you can send a colony ship to it. Depending on your tech, your colony ship might travel at differing speeds, which could lead to all sorts of fun interactions, like these:
You send a ship at .5 speed of light (henceforth "c") to a planet that's one lightyear away. 3 months later, someone sends a ship at .75c to the same planet. Using math, we can calculate that the lattership will arrive at the planet in a year and 4 months, while your ship will take two years to arrive. This means that by the time your colonists arrive, the other country's colonists have been sitting there for a good 8 months and building defenses and that sort of thing. HOWEVER...
If they put that much research into superior engines, then they likely don't have the same strengths in other techs. Perhaps you put more points in military, such that, even though your colonists spend more time in stasis, they can overwhelm the initial enemy. Or perhaps they have inferior infrastructure and biology, meaning that much of the planet is still unoccupied, allowing for multiple colonies.
Another thing that is of importance is communications. Because some of these systems are going to be many light years away, the speed of communications is vital. Suppose both your colony and their colony are coexisting on the planet. Suddenly, a war breaks out between your two factions. If you have faster communciations, you can send a message to your colony quicker, allowing them to launch a surprise attack on the enemy. Similarly, if your colonists take matters into their own hands (Manifest Destiny!) faster communications could let you find out about it before the enemy, giving you time to prepare a response.
Also, travel is very risky. There is going to be a high chance that many colonies will fail, or that you will lose contact with the colony ship. Or perhaps your communications are slow, meaning there is a lot of time between what happens on Earth vs. Farawaycolony I. Or maybe you couldn't economically sustain the colony, leaving the colonists to fend for themselves or die trying. This could mean your colony could have a culture shift, meaning they no longer associate with you (from Americans to Farawaycolonians), and they might try and declare independence, and there could be nothing you can do about it. By the time you prepare a military response, they may already have created another empire in their neighboring region. Remember Starcraft Brood War's plot, of how the Earth forces essentially arrived to try and subjugate an equally armed empire? Funsies.
Also throwing in a fair amount of alien technology (colonists stumble upon alien plasma weaponry and declare a revolt, now what) and xenos of varying technological and ability capacities leads to fun, too. But that's another story.
