Master Quest feels a bit like a proto-ROM Hack. It's a more challenging version of the game specifically designed for players deeply familiar with the regular mode. This is different from a normal hard mode, which might be playable for the first time by players familiar with a genre.

I would love to see more games take this approach to hard mode, but it is an unreasonable amount of development to go into something a minority of players will enjoy.

As for Master Quest specifically... I wish the overworld was changed too. Could also go even further by moving around key items and changing dungeon orders more than they did. But hey, we have real fanmade ROM Hacks for that nowadays.