Isn't "Directed weapons master" allow the proto-everyman? i.e. 3 ranks for 2?
Let me look..
Yeah, it's 3 for 2 in one category, and you pay 50% more for all other categories. . .
That's pretty close to what you asked for up top. . .the effect would be to pay 66% for one cat, and 150% for all others. . for a 9/20/etc mage type that would become 6/30/etc. . .
It's effectively a cost of 6, since it costs 9 for one, then 9 for 2, then you get 3 for free, so it's 3 for 18 or 6 each. . .
Not exactly what you were looking for 5/40/etc. . .but 6/30/etc seems close enough.