I was posed with the idea that all of these big alliances out and about from the get go is not necessarily a good thing. makes things not to single player friendly. My thought was to have a Diplomacy Center that would need both the Ship Yard and Colony to be built and would need resources similar to the Colony to construct. This would add a great new dynamic to the game and make it not be just about being in a big alliance. You could also have the Diplomacy Center upgrade-able by members of the alliance donating resources to upgrade fleet size and other features like increased travel speed or other bonuses.
So my thought was this:
Requirements: Colony, Ship Yard, 60k metal, 40k mineral, 80k workers
Function: Allow for the creation of an Alliance and allow alliance members to take part in coordinated battles and to allow for alliance NAPs.
Start: All special features Upgrade-able through members resource donations
Alliance Fleet Size: 4 fleets max in any coordinated attack. +2 per upgrade
Alliance Travel Speed: -1 Hour per upgrade, max -6 hours.
Alliance Fleet Battle Bonus: Bonus to attacks on fleets.
Alliance Invasion Bonus: Bonus to invasions.
I’m sure there could be more, but this would be a resource expenditure that players would need to sacrifice for the alliance rather than use for their personal gains.