Trading technologies or civ bonuses between two civs and improving both civs as a result?

If two civs could trade up to two techs and/or bonuses with each other (with both civs losing the techs/bonuses that the other civ gains, but gaining the one or two things from the other civ) would any of the possible trades improve BOTH civs?

I tried to think about this for a bit, and it turned out to be harder than it looks initially. First you have to find a significant tech tree gap, then you have to find a civ with the needed tech/bonus that doesn't need it as badly as the first civ does. And then you have to find the reciprocal issue between those two civs. Maybe the difficulty of this speaks to the trade offs and balance of the game already present. What is the best trade you can think of? Please limit trades to a max of one or two techs/bonuses being exchanged in each transaction.

For example:

Persians trade (1) Parthian Tactics and (2) Boiling Oil to the Berbers for (1) Heresy and (2) Kasbah.

Kasbah could help a Persian boom civ produce elephants faster and Heresy would help their keep their cavalry (and elephants) from being stolen by monks. The Berbers would gain Parthian Tactics for both their HCA AND their Camel Archers (+1/2 armor and bonus vs. pikeman line) and while Boiling Oil would be underwhelming, it would at least help keep their castles alive longer to produce their more powerful Camel Archers (which can't help very much in defeating rams). Losing Parthian tactics would only minimally hurt Persians (since they lack bracer anyway) while losing Kasbah only minimally impacts Camel Archer production for Berbers, while significantly affecting the War Elephants long training time. Losing Heresy would hurt the Berbers, but not as much as most cavalry civs, due to their -25% cost of cavalry.