In principle it works for 6th chords as well. In g major you can find gmaj6, Dmaj6, Am6, Cmaj6, for E, B and F# the 6th that makes up the 6th chord is missing. So you can build 6th chord for those in the g major scale.
Augmented is a bit more tricky since augmented only refers to a raised 5th in a major chord, Not in minor.