Here's my idea for a competitive multiplayer mod:
- Allies - Other players are counted as enemies by default, unless the players accept each other as allies. Only allies can be remove your buildings. Otherwise they have to be shot down. Turrets target player enemies
- Neutral - Players should be able to be marked as neutral so turrets don't shoot at them, but your gates don't open for them either
- Spawns - Separate the spawns more, so players don't spawn right next to each other
- Separate maps and research - Ingame exploration/research should be per-alliance rather than the same progress for every player
- Trade Markets - This would be the economy of the multiplayer. More information on this below
- Scoring - The score could be based on current assets including currency, and the amount of biters killed either separated or combined (maybe a military score and an economy score?). This will give players an either increasing goal to beat
- The currency used could be based on the existing currency
- The price of items in the market should be based on the current amount of items available in it, the more items in the market the cheaper that item becomes
- Raw items (such as iron ore) will slowly increase the markets supply over item, even if no player is selling those to it
- The market will have it's own two inventories, one stores bought items, and the other stores items waiting to be sold
- Inserters that take items from the market will take from the bought items inventory, and when inserting it will place them in the for-sale inventory
- You should be able to set a minimum and maximum buy/sell value for each item.