Even if it duplicates PAL research, I'd say we need to go Printing Press -> Replaceable Parts -> Rifling as soon as possible. Remember, our core strategy at the moment is based on a huge army of drafted conscripts. The sooner we can turn them into rifles instead of oromos, the better.
The one reason to grab Economics would be to get the Merchant there, so that we could save him for Sid's Sushi. T-Hawk's favorite corporation could be critical in the late game, especially if we decide to go for culture. If the Merchant is still there, it's definitely a possibility.
We should try to do everything possible to get Banana to cut all trade with PAL. If Donovan trades any more techs with PAL, it speeds the runaway team further ahead, and seals the doom of us both. It's critical that we convey to Donovan the importance of avoiding all trades, even ones that are heavily in Banana's favor. Emphasize the fate of Rabbits: "You will be next!"