Just a random thought. While intervention is a very good card (basically a must for china) its a very “more” kinda card that doesnt provide strategic benefit ( though that can be said for a lot of chinese shipment)
So the idea for buffing it is simple.
Intervention now sends an Expeditionary Force (the second tier army) of the consulate ally.
So:
Brit - 9 Redcoats, 1 Falc
French - 3 Gendarm, 3 grens
German - 3 Dopps, 7 Skirms
Russia - 5 Counter dragoons, 1 culv
Otto - 3 Delis , 7 Jans
Port - 11 Xbow, 1 culv
Japan - eh maybe the same 10 Yamabushi but add 3 more shinobis?
Spain - 9 Rods, 1 Falc
These shipment for the most part will be straight buffs to the existing Intervention so to keep it balance slapping on a 200-300 coin cost seems very rational.
It even slows down the China deathball but maybe can give it a bit of oomph when you push.
This gives a lot of incentive to save export since now 800 export + intervention = a very deadly push and gives all 3 asian civs a path to something like a 2 falc timing.
It can even be useful in defensive situation by getting the culv which while doesnt 1 shot can heavily threaten artillery