Will this pulley arrangement keep this kayak level when hoisting?
No, it will not, at least if the load is balanced as shown.  The leftmost part of the kayak / canoe, having a snatch block on it, will experience twice the lifting force as the front of the kayak.  If the kayak was moved towards the left, it could potentially balance out, but you will likely need to do some manual adjustment as the kayak is lifted.