Plus if they went Sloth 3, they get 55% resources, and Prod 3 gives you 145% resources, which is over 2.5/1 resources in your favor. Now the battle is at less than a 2/1 ratio, and the samurai armor starts to show its worth in an archer fight.
BUT, be that as it may, I agree that just making archers won't cut the mustard. While they are excellent missile troops, it still comes down to the fact that the strength of Jomon's conventional army is in their shock infantry. Practically every one of their units is a slight variant of a shock troop. Personally I would make armor/protection spells the #1 buffing priority. Who cares if they can hit you with arrows if you have 20 Prot, right?
Also, you have access to gobs of 2S mages, who can spam Body Ethereal until the cows come home. 20 Prot ethereal samurai should dominate the early game. Also, these should likely be your primary battlemages after some time. Once you can field enough of them to set up strong Communions, all those scattered paths at 1 suddenly become endless diversity of top end evocations. Want to cast Blade Wind? Easy. Want to cast Thunder Strike? Got it covered. Need some Magma Eruption spam? Gotcha.
Now I think I want to try these guys out again, I love the flavor of Jomonese culture.
