AbdulAlhazred
Legend
How about the philosophy that heros should be awesome because of themselves not their toys? i think that is why daily limits centered more around the hero make sense.
Think of it this way - My hero has 1 to 4 dailies of personal power AND they limited item dailies to be 1 to 3 dailies.
Your personal game took the powers items and personal power provide and melded them into boons which is rather huzzah but they are juggling where the awesome comes from and you don't have to.
Well, as you point out, my operating philosophy is that its up to the players and the GM, by way of how they unfold the narrative, to arrive at an answer to this question. So, for example, there is a boon in HoML, 'Student of the Sword', which has a couple of "you wield your sword competently" powers you can pick up from it, plus you get proficiency with a type of sword.
You could recast that ('Embody' it in HoML parlance) as an item. Lets call it a 'Sword of Expertise'. It would have the same two powers attached to it, and presumably you'd wield it with proficiency whenever you used it.
Which of these embodiments, Training, or Treasure, will you use? Or you could pick Imbuement, you become a Student of the Sword due to being exposed to some magical force, etc. Maybe it was a Grant, one of the gods simply granted you sword swinging chops. Finally you could simply 'manifest' a boon, through some process that isn't covered by the other possibilities (IE a birthright or something).
GMs provide the narrative response which indicates the manifestation of a boon, but usually the players are selecting what sort of a thing it will be by how their characters act during the game.
So, yeah, once we move outside the realm of strictly talking about 4e's magic system then there are a lot more options and less constraints. Of course you could revamp 4e to work like HoML does in this respect. It probably wouldn't be THAT hard...