I'm multiplying each rating by a weight, and adding those up. For example 5 star ratings are multiplied by 2, and 1 star ratings are multiplied by -3. In sorting, packs with 1 star ratings will go near the end of the list, whereas packs with 4 and 5 star ratings will go near the start.
It's slightly more organic than the previous sorting method, which was by rating average and number of ratings.
The below image gives an idea how this works:
