I think one way to approach it might be to scale the difficulty of identifying based on the item’s rarity.
Common magic items should still be doable for free as a ritual. While higher tiers should require spending slots (which means having the spell prepared) and upcasting higher slots for higher tiers.
From that rough foundation, you can then layer a few variants:
1. If you want to put an emphasis on the mystery of magic items, then let the slotted Identify fail outright if it was not sufficiently upcasted. Characters can always retry with a higher slot if they really care to know what it does.
2. If you think 1 is too punitive, then let the free ritual reveal the rarity tier, so then the next slot spent can be guaranteed to be high enough (assuming characters can cast it at all, obviously).
3. If you want to get really fancy, some items might have different properties that belong to different rarity tiers. For example, a +1 weapon is uncommon, while a vicious one is rare. Let’s say a +1 vicious weapon was rare. You might be able to know that it’s +1 with a low level slotted identify, but need to wait a few more levels before you’re able to upcast sufficiently to discover that it’s also vicious. Under this system, presumably, you would not be able to make use of the vicious property until it’s identified (e.g., imagine there is a command word to activate the viciousness, or you need to hiss or jump and bump your heels in the air or whatever, and until you know to do that, you can’t use the property).
4. Consider whether cursed items have any special twist. For example, maybe they have a beneficial property at a low rarity tier, but the fact they’re cursed gets revealed only at a higher rarity tier. But as soon as you attune you’re cursed regardless. Will you make use of this +1 weapon now even though you’re not high enough level to know what else it can do? Maybe it’s +1 and vicious. Or maybe it’s +1 and makes you go berserk as soon as you see a priest of Corellon. Who knows!?
In other words, make players work for it, and let them have the feeling of delayed gratification. But once they do the right thing, let them know what the thing is, and move on.