yeah, save the seals for mythic week and then start “the grand opening” with seals first 
you may save more gems and other keys that way and still get a monthly supply of guardians
about gold keys,
i think im going to go with “2-kingdoms schedule” for gold keys:
- gonna mass open all gold keys at every other new kingdom release
- while at the other kingdom release ill only open a few to find at least one copy of each new (low rarity) unit
due to calculations i found at a topic related to that - i found out that gathering all gold keys per one kingdom release (without reserving extra gold for it) wouldnt suffice so this hopefully will be my way to make it up