Cardistry is meant to show off. You want your audience to see well the moves, flows and displays. You are looking for visual effects. So, I think the best cardistry decks need to have high contrast backs, and faces if possible, or have interesting back designs and colors that blend well in motion.
Some of my favorite picks:
The Virtuoso decks fit that category, colors are blending together well when cascading, fans are well-defined.
The Mystery deck has thick lines that fit well for cardistry too.
The Black Fontaines surprised me. In pictures, the design seems too simplistic, but the handling is great, and the back has very good contrast for cardistry.
A nice discovery for me was also the Alice in Wonderland Cardistry Edition. The backs have a nice classic touch, with high enough contrast between the white borders and the dark back, but the secret weapon of this deck are the simplistic faces: clubs and hearts are white with black and gold pips, but spades are all-black, and diamonds are all-gold, which lead to great face fans (
https://instagram.com/p/2j2z_tklA2/).
And who doesn't like the smoke and mirrors...