| Becuase really all I want to do is trade the AIs Starbase Mining Research 49 in my territory for my Starbase Mining Research 132 in there territory. |
Never tried it, so can't say for sure, but I doubt it is possible in the current version. It usually costs 2.5-3million BC to buy a fully upgraded mining starbase now - can't say I've ever even considered selling or trading one away, so no idea what the AI would give for them.
I agree that in that type of situation (assuming both SBs are at the same upgrade level), an equal trade should be possible. Maybe the value that the AI attaches to player-owned starbases needs to be revised and brought into line with the value it assigns to it's own. That said, I'd happily give up 4 research resources for one military or economic (especially after I've completed the tech tree) - so maybe even that is still exploitable to a certain extent.
I would still be against planet for planet trades though, because it really would be too easy for a human player to exploit. I think writing AI code to get round that exploitation, while possible, would result in a huge performance hit.