Once upon a time, I planned a Zelda game in OpenBOR, a game much akin to Guardian Heroes and the D&D beat em ups. The game's controls would have relied on command inputs for each of the characters's special attacks, which improve as characters level up and more moves are added.
The Playable Cast:
I would have largely taken from Hyrule Warriors, although most of the villains would be post-game unlockable characters (although Cia is simply unlocked by defeating her, given that she reformed in the 3DS game), while Ravio and the King of Red Lions would get the axe. In addition, I would have added additional characters, such as;
* Saria (notably suffering from a curse that would turn her into a were-korok under certain conditions.)
* Hilda (to replace Ravio, mainly. Her inclusion spurned most of the other characters.)
* Princess Styla
* Fado (suffers from the same curse as Saroa)
* Samus Aran (post-game unlockable)
(Yes, it would have been Harem Warriors all over again)
The level system:
Like in other OpenBOR games such as Super Final Fight Gold, characters could level up to increase HP and MP. Unlike those games, they would also unlock new moves and improve other stats. Players were able to level past twenty levels.
Locations were to be taken from many Zelda games though the years. Each level had specific quests for players to embark on, many based on specific games (some games would be encapsulated into a single quest, such as TriForce Heroes)