Oops. Looking at it and the other civs, trade could be a 3. Most of the Mongol attacks were revenge attacks for having their trade people killed when attempting to initiate trade with other nations. They also protected trade routes like the silk road and what not to allow trade to flow safely. They valued trade quite a lot.
One could arguably say that production should be next to nothing, but that's a limitation of the game mechanics moreso than anything else. When the combat engine can result in 3 outcomes - win, loose or draw (no one dies) - then production could be reduced. The Mongol units should be hard to kill (able to disengage from combat if things go south) but until that happens, the military much resort to production in order to give it a decent military. Ohhh I dream of the day of a 3 outcome combat engine...