The Top 10 sets close to completion has now been changed to the Top 100. This should give ample room to find sets that are missing more than just variations.
Dixxy, for collections, the completion percentage is based on the "Total Cards" field which usually doesn't take into account errors and variations, so looking at your example of 1990-91 Pro Set Hockey, the set should be complete at 705 cards and looking at your collection, it's actually displaying at 100% complete:
Dixxy's 1990-91 Pro Set Hockey Collection
Thanks,
The Trading Card Database
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