^THIS
or
Do not merge. Instead, remove duplicates in different shops. Newbie friendly items remain on shops with easy-to-obtain currencies while end-game/stylish/collectibles on the others.
For example:
V4p: Punk beanie, Satyr, Death Weapons, Donation Clones, v4p-exclusive life steal helm, v4p-exclusive delay wing, etc. (Sprite doesn't matter. Newbies can't be choosers)
Include some items for old players so they don't stop voting.
DQ Tokens: Bound Cards, Collectibles, etc.
DM points: Consumables, Craftable Equipment, etc.
Battle Badges: Glorious Equipment and some donation items with exclusive sprites, etc.
Hero Coins: Gems, Rare Sets, Zeny Bags, Shields (Evalach, Toth, Aeneas), Keeper's Set, etc.
Combat Coins: Combat Equipment, Obelisk Set, etc.
Division Coins: Division Events consumables, Elite Gloves scroll, Division Exp Scrolls, etc.
Donation Token: Has everything (with exceptions). Those who donate have the freedom to choose since they keep the server alive.
No shop should have the same item sold in other shops (with exceptions like Death Weapons, etc).