Currently in my overview page I have it filtered to Deck-building mode and have noticed that it suggests opening packs that I already have 2 cards of all variations (which I have filtered on - Filter is just Deck-building mode on and 2 number of cards wanted).
For example, Genetic Apex shows that I have 2 of all 226 cards (as well as all 61/61 for Charizard, Pikachu and Mewtwo and 43/43 for Every pack), but still suggests that I should open a Charizard pack (3.7%) or a Pikachu pack (1.9%)
Edit: Adding my collection link here in case it helps!