Okay I can see how this could be used ;)
Reasonable PC :Hey META PC #1 do you still have that goat milk we got at the halfling village before the banshee encounter outside the Temple of Vulsadoom
Excitable PC: And I am Priest! I place a rag in my pants and start jumping up and down.
Meta PC #1: I am sure I don't still have that with me, that was like a 4 years ago in game time.
Meta PC #2: *snatch* You still have it on your character sheet. So we are a good.
Roleplaying PC: What type of strange and wonderous item could this be....surely we must use it for the good of the people allow me to veiw these ancient tomes. *a moment later after viewing the hand outs "seriously Ted?"*
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GM (TED): And the Hyperion mines are beneath Vulsadoom's temple, looks like I will get to use the map after all.
Seriously I think this a nice write up and a fun read. Plus players tend to like magical stuff they can manipulate and fetishize. But my the luke warm response to these types of items is that they bestow things on the character without bestowing or coming with any character growth. Yes the character may have wings or can see ghost afters a swig from this safe bottle, but that ability is dissjointed from his person. While questing for these items and having the manual for this item will increase the player's connection to it, it does not itself justify this things exsistance.
Other items like your crown for example, have existance and a personality the player can manipulate and use but won't change the player unless they want it to. Perhaps I am wrong about this and it would be a really fun item, but I think it might be overly complex and with too little a story hook to justify the dramatic effects (even positive) that it will have a player's character.
Also technical: how will the players know what powers they are removing with out a meta-game pick the item