If you are keeping the Evo, maybe go with something more different from most of the boards you listed in order to start building the quiver.
Evo is the most free-style of these boards, so maybe go more freeride - that would be the Cobra. Only issue with that is the switch riding and landing, especially in pow.
Also consider the Heritage. You will sacrifice playfulness and butter-ability but you will gain stability and big-mountain capability for your off-piste riding.