Wow, that's pretty cool. I wonder what happens if your discounts total up to 100%?

Decorated Hero: –20%
Drillmaster: –10%
Lanista: –10%
Master Smith: –10%
Mercenary Captain: –10%
Priest of Vulcan: –10%

Drat, looks like a max of –70%. Anyone up for further testing? You could add a few more ancillaries/traits and then cheat to get them all. I expect there's a hard-coded cap of some sort, but you never know!

-Simetrical