Assassin: Crit dmg, +crit on race cards

So I made a equip crit sin and so far I only have triple crit jur which while nice has low damage so I wonder if those +10% dmg +7 crit per race cards are worth it and if that +7 crit is also doubled by katar.

And if they aren't worth it, should I make double element/race/size, 1 SS card jurs?