There are a number of resources out there that allow you to plug in your decklist and get a breakdown of what percentage of your cards need specific colors of mana, what the average converted mana cost of your cards is, and other helpful information (Im partial to Tapped Out personally)
Many cards in this release care about historic cards, spells, and permanentsthat is, cards, spells, and permanents with the legendary supertype, the artifact card type, or the Saga enchantment type
Conversely, Steel-type Pokmon boast resistances to many types of attacks, making them formidable defensive options
All blanks will also be 1.5x the size of my original blanks, or about 540 x 750 pixels, assuming an average pixel size of 360 x 500