I'm designing a board game about space colonization. There is a simulated solar system with planets that have different compositions, atmospheres, temperatures, and biomes. Each planet has a grid to move your populations around on and build buildings. The goal is to colonize the most planets.
The problem with this is that once you colonize a planet, no one else can come to it. This diminishes player interaction, which I want to have a part in this game, because who likes a game where you make one decision (which planet to start on), and then remain isolated from all other players as you choose which planets to colonize next for the rest of the game? I'd really like to add some player interaction without increasing the complexity of the game too much, because there are already a lot of mechanics to it. Any ideas about anything I could add to the game to increase player interaction?
Thank you for the advice, I understand I didn't give many details. I like your idea of taking away a bonus from colonizing a planet if an opponent is already there. This actually does happen in my game. There are certain resources that are distributed to each planet that can only be taken once, and that does give you a bonus for being on a planet first.
So First of all, in my game you are in control of groups of people (populations). They move around on a planet, collecting resources and building. They may build a rocket, board it, and travel to another planet. To colonize a planet you must have a population of at least 4 people on it. How this works practically, is there is a main board showing the solar system with all of the available planets for the current game, and then around the central board are separate planet boards where people may manage their populations.
Players already want to colonize planets near their own, since you may only start colonizing planets within a certain habitable zone until you upgrade your gear. I suppose this would probably lead to combat. I'm going to give up the idea that you may not go to planets that are already colonized by other people. I think this would be best because then there is more player interaction, and players have more decisions: they could go far away to an planet that isn't colonized already, or they could go fight for one that is colonized by someone else.
For the combat system, I think I am going to not make it luck-based, since there has not been much luck involved with the game so far. Each turn a population may use up all of it's "humanpower" to perform certain actions (a population has as much humanpower as it has people). For example, if a building costs 2 humanpower to use, and you have a population of 6 people, you may use the building 3 times in a turn. So I'm thinking that it should take one humanpower for one person to attack (populations can only attack bordering populations in the grid on a planet), but since a population can move up to three spaces on a turn, players can strategically hit-and-run. This combat system also allows for populations to strategically surround and corner enemy populations on a planet, or force them to move back, allowing even more strategy into the combat system, and making it more realistic. Thank you for the suggestions, they really helped.