I was hoping to complete the commons for a set by opening packs, but it looks like I keep getting duplicates instead? Is using wildcards going to be the best way to complete the commons for that set?

Seems like they could either A. have common slots fill with missing cards first, or B. have duplicates be some small number of gems instead, like they do for rares and mythics (or ideally, both A and B).

What’s the point of opening my 5th, 6th, 7th etc of a common?