Makgeolli

Hello from Tampa. Spent 10 yrs. working on contract for KAL.
Experienced culture and good friends. After hiking the mountains around Seoul would stop for some makgeolli, warm tobu and kimchi. I have learned to make makgeolli from Maangchi’s cookbook. Very authentic and helpful to me as I have a need for Korean food.
My question is on the variations of makgeolli as in the addition of black beans and/or sweet potato. Also, the addition of ground rice a couple days after the initial mix. Maangchi’s recipe was easy to follow compared to other internet sources.
Any input appreciated.
Thanks