2013 Cartels are supposedly softer than in years past, the it still has its "7" flex rating as it always has.
If you KNOW you are carving a lot now and will focus on only that --> get a stiff binding, 7 or higher on the 1-9 flex scale. If you want to do anything else and keep on working on jumps/try to diversify your riding style, get something on the mid-stiff side, like the Genesis (6). Problem with super stiff bindings on jumps is the slightest miscalculation in posture/body movement can make your take-off all wonky since the bindings are so responsive. Same goes for stiff boots.
I ride Ions with my Lib T. Rice pro and I have Burton Prophecy bindings, which have been discontinued for the Genesis bindings. Perfect blend of jumping and carving ability IMO. Not so hot for boxes and rails.