I think putting a limit on how many you can buy would be fair. I agree people shouldn't be able to boost to 34 out of the gate, but light is for weapons too. If it's too difficult to get it'll be pointless to upgrade the old weapons to new damage levels. With all the new weapons and armor coming out materials will once again be needed, motes included. You can reforge vendor weapons and they'll still need to be upgraded. None of the materials currently in game will be obsolete.