I wonder about diplomacy. I really am hoping they take that to the next level. It has me thinking about defensive pacts, and friendship, and un-claimed territory.
Personally i always thought the colony expansion process should be slower. On smaller maps especially but even larger maps can get filled up rather fast, really before any decent fleets are built.
It has me wondering if perhaps diplomacy can be part of the answer to slow this down. My thinking is, marking planets as territory, or with the idea to colonize later. take for example a smaller planet in your systems, that you already own planets. Having to make a choice do i colonize, or not. How the other AI's view those actions. Basically deepening the idea of building in opposed territory, but even things just outside could be considered owned.
But what about making pact's with neighbors, or minor races. I would love to beable to say things like i am protecting this race, or planet, or area.. and coming in could mean war. A rating of power, and willingness to keep up your side of things would be part of the play. But right now, i find it hard to give any warning to other races about there actions.