I can't say I've ever heard "kin" used in everyday English speech. The only generally recognizable example word I can think of using it is "munchkin", which either refers to certain small residents of Oz (from "The Wizard of Oz" lore) or the name Dunkin' uses for the confection more generically known as a "doughnut hole" (which if you're not familiar with it is essentially the doughy center of the doughnut removed to make the hole and in my opinion should be called something like "inverse doughnut holes", although no one else seems to feel as strongly as me about it).

I had to Google what "augmentative suffix" was; despite having taken several years of Spanish in middle school and high school and being aware of the concept, I somehow hadn't heard that term before! I don't think there's anything common for that in English; the only thing that springs to mind for me is the prefix "big-ass", which probably isn't different enough from the typical adjective used for this purpose to qualify.