Don't bother with pentamelding at this point. They will likely have new level 71 gear, level 72 mainhand and level 73 offhand that will only be very slightly weaker than the current BiS. And you can level up to 75 in no time. So just meld CP onto yourself. Custom Delivery is a powerful thingy that will help you get most of the yellow scrip tools (unmeldable), and you should just stick with those for now. You're also free to use the yellow scrip hat, chest and gloves since they can't really meld many CP anyway. But for the belt, pants, boots and accessories, I highly recommend using the crafted ones, and max out CP with melding.