What makes a good proxy Prioritize readability: correct name/mana/cost, clean rules text, and art that doesnt muddy the frame
These decks are also well-suited to fight discard via counterspells
When Prophetic Prism is legal, it usually ends up being in one deck or another, and with all of the benefits Kaladesh offers from having artifacts on the battlefield, I think you can expect to see Prophetic Prism around for the duration of its legality
There is a sub-lifegain theme to the deck, with cards like Soul Warden and Guide of Souls both gaining life when creatures enter
This allows you to maximize the effectiveness of your plays
I aim for at least one landcycler in each of my colors, as well as two fixing lands per color Im playing