A data management method includes assigning data buffered in a first memory device into at least two different groups for transfer to a second memory device. At least one of the different groups has at least two units of the data assigned thereto. The data is transferred from the first memory device to the second memory device in a sequence according to a respective priority associated with each of the different groups and in group-by-group manner such that units of the data assigned to a group having a higher priority are transferred to the second memory device prior to units of the data assigned to a group having a lower priority. Related systems and methods are also discussed.