I've found a majority of my etched patterns in the beginning courtyard ... In fact, I can't even clear half the courtyard without getting named, and several cases where I spawn two named in the same pull. Should try clearing there for some
Can't really compare it to DSK3 either... you basically get the bloods for doing the bosses because there is no trash in the zone. VT is a little different in that you actually have to go out of your way to get the minis to spawn. Sure, it's a little more challenging to get the gear since you skip DSK3, but I wouldn't qualify re-auging as a hassle, especially with how easy it is to get some HoH augs to put in there. Idk, just my opinion... never really thought about the drop chance when I was looking for some.
Maybe add etched patterns to boss drop list at the same drop chance as the minis?