Magic actually has depicted some male angels outside of Amonkhet, though the first, Gabriel Angelfire, is from early on in Magics life, before many of the design conventions Wizards holds themselves to were even established
It's unclear whether this was the most necessary of the Slivers, but it was the one that frustrated the most opposing plans to deal with the problem and even opened up new game plans when the card advantage resulting from saving your creatures could allow Sliver decks to go the control route when backed up by counters and removal spells
For instance, players could use the black-green fetchland Verdant Catacombs to search the deck for Temple Garden, a forest/plains-type white-green shockland
MTGprint will be the most straightforward one out of the two
Lifegain in black and white can come in big chunks, and we're not just talking the three life from the food Sorin, Ravenous Neonate will generate
Bennie Bracks, Zoologist Bennie Bracks, Zoologist gives you a card if youre consistently making tokens, which is a good incentive to go that route