The Samurai Archers only cost 3 more gold a pop than normal samurai, but they have reduced attack and defense (especially after standard Samurai were boosted.) I think that the change leaves archers in a support role and still allows the player to amass enough to do some good as pure archers.
I think something that many people may be missing is that Samurai are very vulnerable troops. Without shields and a prot. value significantly less than even standard heavy infantry it is very easy for them to meet death on the battlefield. If you look at other races standard HI, like the Arco Hypaspist, you will see the difference is essentially 4 less protection and no shield to defend against range- this is a very big disadvantage. In order to make them worthy, they must either a) cost less than their adversaries or b) make up for it by having high att, def, or str values.
I'm wary about attribute pumping because there really isn't any way to justify a nonmagical recruit fighter having superhuman strength or skill- 13 is as high as is plausible for foot soldier samurai. Thus, I feel the Samurai's low cost and high stats (13 av, 12 dv, 11 str, 16 gold) are more a counterbalance to his vulnerability on the battlefield (Ashikaga has access to air magic for SoS, but it is expensive) than an unbalancing factor.
In short, this is my excuse for not making him much more expensive.
Genin, on the other hand, are comparable to mini-Vans. They now cost 40 gold.