opening up DiplomacyDefs.xml & setting <Behavior>ResourceAndTechTrade</Behavior> to the same numeric value as <Behavior>WillSurrenderToYou</Behavior>does sort of a nice job of almost sorta it at least in the 50ish turns I played, but I fully expect that it will fall apart when the ai starts to threaten me because they have a larger stockpile of tiny hulls with a laser or something.
I was testing with informative diplomacy 1.4 installed so stock might differ somewhat.