What will be waiting at the end of each dungeon? Let's see what a few of the candidates are...

* Triforces
The old diehard. Personally, I think NeoFirst should assert to its players that, thanks to the Subscreen Editor, no longer must the Quest Token be a fragment of the Golden Power!

* Zelda 2 (you put crystals into statues to break a barrier somewhere)
This differs from the other suggestions in that you lose the Token rather than receive it.

* Spiritual Stones / Goddess Pearls / Pendants
Zelda theory says that the Spiritual Stones of OoT have shapechanging properties, and that the Stones, the Goddess Pearls collected by the Hero of Winds and the Pendants collected by the Hero of Triforce/Light are the same items adapted to their respective ages. However, tradition also holds that the Spritual Stones are always used to unlock the Master Sword. This may cause a problem.

* Master Sword fragments
In this case there'd just be two of them, for the first and second dungeons. Remember that the "Master Sword" doesn't have to be the Level 4 Sword if we don't want it to be.

* No token, just another piece of equipment.
A bold suggestion! The downfall of a major dungeon boss rewards you with a new power that is vitally necessary to enter the final dungeon!

Any other ideas?