Oooo these are some really good suggestions, it’s good to have someone with more PvP experience weigh-in on it! 
I really like your suggestion for the Halloween Mask being like a Vold skull, hiding armour but leaving the head is a cool idea. Same for the Cozy Lantern and adding a special ability to the Bow, both could be very epic 
For the Wizard’s Wand, I envisioned it more as a transport item, say in the Nether, or if you wanted to move around a biome rather than between biomes with /rtp. But using it for PvP is also a funky idea 
Thanks for putting in the time to give your thoughts on all the items 