There's also the fact that any given army should be *less than 1%* of the entire population of a kingdom, else the kingdom would turn bankrupt. So with a force of 10K soldiers, you'd expect to see a kingdom of at *least* 1,000,000 persons. Assuming that that number is anywhere near accurate, and the population isn't actually even higher, we're looking at 2,000 "magic capable" persons.
Now, 3/4 are gone off the top as undiscovered/only minor traits/blocked from magic for being near iron (dubious that that many would have that happen due to the low numbers of smiths and soldiers needed for t…