Do I report refunds (goods I purchased and later returned for my business) and miscellaneous bank credits under other business income?

Goods returned are subtracted from the category those goods were reported in the first place. If those goods were for resale and you enter them as Purchases then the return is subtracted from Purchases. If they were Supplies then returns are subtracted from Supplies.

Miscellaneous bank credits can be reported as Other business income.