A console-store bundle should tell you what it adds to your library before asking you to pay. If you already have the base game and one expansion, the useful question isn't how many items the bundle contains. It's which of those items would actually be new to you.
We'd like ownership-aware comparisons to become a basic storefront feature: a readable list showing what you own, what you can currently access, and what the proposed purchase would add. This is a design proposal, not an audit of a particular console store. It starts with a simple principle: a returning customer should have less homework to do, not more.
Imagine a fictional adventure sold as a standard edition, a complete edition and a separate expansion pass. You bought the standard edition a year ago, then picked up the first expansion. Now you want the second. A useful store would begin with that situation, rather than expect you to reconstruct it from three promotional descriptions.
The complete edition's page could mark the base game and first expansion as already owned. It could highlight the second expansion as new, with optional costumes listed separately. You could then decide whether the remaining content interests you before getting distracted by the size of the advertised package.
Compare what changes for you
The comparison should explain playable content before cosmetic extras. A new campaign, a soundtrack and an outfit might all count as one item, but they answer different wants. Someone looking for another evening of missions shouldn't need to infer the bundle's purpose from a long list of bonus names.
That doesn't require the store to decide which extras are valuable. A soundtrack can be the reason someone wants a particular edition. The goal is to describe each component plainly, then show whether the account already has it. Let the player make the judgment with the relevant information visible.
Prices need the same restraint. We'd want the page to show the price of the bundle alongside the available ways to buy its missing playable content. If the bundle costs less, say so. If buying the missing expansion separately costs less, make that route easy to find. Neither result should depend on the customer doing a subtraction exercise across several screens.
This isn't an argument that every bundle must provide an ownership discount. A publisher might choose a fixed package price. It should still be possible to explain that price honestly: these are the things you have, these are the things you'll gain, and this is the amount you're being asked to spend.
Keep access separate from purchase
The harder design problem is the meaning of “owned.” For our proposed comparison, an item bought on the current account should look different from an item available through a subscription or another account's sharing arrangement. A single reassuring checkmark would conceal the distinction we're trying to make clear.
A useful label would describe the basis of access and any condition the store can verify. It shouldn't promise permanent availability, guess what someone owns on another account, or imply that an installed game is proof of purchase. When the store doesn't know, a short explanation is better than a confident answer.
Physical copies create another limit. We wouldn't want a storefront to pretend it knows every disc or cartridge on your shelf. It could let you compare editions manually without converting that selection into an ownership claim. The interface should distinguish information you entered from a purchase recorded on the account.
There are reasonable costs here. Edition contents can be complicated, and an inaccurate comparison could be worse than a plain list. We'd start with individually identified games and expansions, make uncertain matches explicit, and provide a route to the full product terms. A modest comparison that gets the important distinctions right would be enough.
Until a store gives you that clarity, make your own short list before buying an upgrade: the game you have, the extra content you want, and the account you'll use. Compare the price of that missing content with the bundle's full price. Treat bonuses you wouldn't otherwise buy as optional, and choose the package that gets you what you actually want to play.