All of Karmaka's cards will be poker-sized, 63x88mm. (The same as Magic the Gathering and many other popular card games.)
We seriously considered making them bigger - mainly to show off the art - but in the end we decided not to. Tarot-sized cards simply felt too big to us (and the many people we asked). We actually really liked something in-between, around 70x100mm (the same size as in 7 Wonders) but this had several problems:
– Non-standard card sleeves. We didn't want people to have to hunt around and buy custom sleeves for Karmaka.
– Cost. The bigger, non-standard size meant significantly higher manufacturing costs, which means we'd have to charge more, set a higher goal for the Kickstarter, etc.
– Bigger game box. Bigger cards means a bigger box, also increasing the manufacturing and especially the shipping costs of the game. It'd also take up more room on people's shelves, be less portable, etc.
In the end, we're really happy with how the poker-sized cards (in our prototypes) look and feel in hand.