Instead, start with an item that seems ordinary, but has some history behind it. Maybe it came from your ancestors, or as a gift from someone you admire, or maybe you forged a sword yourself for some worthy goal. It might be an ordinary shield you just REALLY like and that's it. Or your favorite set of thieves' tools. Any item, really.
I'd would probably allow for only ONE nonmagical item per PC to be attuned at a time. Of course, there should be an in-character explanation.
The usual rules for Attunement apply.
AttunementHere is the twist: every time your gain an odd level, roll 1d6 for every nonmagical item you're attuned to, and 1d10 for each magic item. If you roll a 1, the item becomes better somehow.
magicitems require a creature to form a bond with them before their magical properties can be used. This bond is called attunement, and certain items have a prerequisite for it. If the prerequisite is a class, a creature must be a member of that class to attune to the item. (If the class is a spellcasting class, a monster qualifies if it has spell slots and uses that class’s spell list.) If the prerequisite is to be a spellcaster, a creature qualifies if it can cast at least one spell using its traits or features, not using a magic item or the like.
Without becoming attuned to an item that requires attunement, a creature gains only its nonmagical benefits, unless its description states otherwise. For example, a magic shield that requires attunement provides the benefits of a normal shield to a creature not attuned to it, but none of its magical properties.
Attuning to an item requires a creature to spend a short rest focused on only that item while being in physical contact with it (this can’t be the same short rest used to learn the item’s properties). This focus can take the form of weapon practice (for a weapon), meditation (for a wondrous item), or some other appropriate activity. If the short rest is interrupted, the attunement attempt fails. Otherwise, at the end of the short rest, the creature gains an intuitive understanding of how to activate any magical properties of the item, including any necessary command words.
An item can be attuned to only one creature at a time, and a creature can be attuned to no more than three magic items at a time. Any attempt to attune to a fourth item fails; the creature must end its attunement to an item first. Additionally, a creature can’t attune to more than one copy of an item. For example, a creature can’t attune to more than one ring of protection at a time.
A creature’s attunement to an item ends if the creature no longer satisfies the prerequisites for attunement, if the item has been more than 100 feet away for at least 24 hours, if the creature dies, or if another creature attunes to the item. A creature can also voluntarily end attunement by spending another short rest focused on the item, unless the item is cursed.
Maybe start with a +1 bonus, then +2, etc. Add extra damage against dragons if you're on a quest to slay dragons. Give the player some choice. Require special materials or new quests if you want to. You might prefer rolling every level, or every four levels, etc., as you wish.
You can still combine this with the usual "find progressively better magic items as you adventure" - even found items can improve with time, if you attune to them.
Could the PC give their items away? Well, it would be missing the point, and also sub-optimal, but why not let them? Especially if a PC dies and a new PC want to continue the dead man's quest, etc. Sounds like a good idea.
If you want to limit that, make the item lose some of its power when changing hands. Only high-level heroes leave legendary items worthy of notice.
I see a lot of advantages to that rule, but one thing that comes to mind is that I know one character (Rogue) that played trough a whole (published) module but found no magic weapons with finesse, only plenty of monsters that are outright immune to nonmagical attacks. The entire group is level 10 and everyone else has magic items (or just spells) since level 5.
There is also this player tendency to pay attention to things that have no special importance or powers. "So, this is the shield of the last guy that fought the tyrant? I'll take it!". Why not let players CHOOSE what is important and POTENTIALLY give it a benefit?
[Giving it a benefit AUTOMATICALLY might be a bad idea, but I'll not go into this here.]
In short, this gives players meaningful choices. I like it.
Anyway, let me know what you think in the comments.