VGM Music Loops: How Short Is Too Short?

[Koh]

Something I've been thinking about since last night.

Often, many older games on 8-bit consoles are criticized for having short and repetitive music (for example, the first Zelda dungeon theme that plays in all 8 main dungeons).  But what would be the ideal length of a track for video game music?

I will say that the later remixes of the Zelda 1 dungeon theme helped a lot by lengthening the track.  For comparison, some links below.

Zelda 1 Dungeon Theme:  https://www.youtube.com/watch?v=cMssCMqMHuk
Link's Awakening DX Enhanced Mix:  https://www.youtube.com/watch?v=uN5EXLqG3Z8
Minish Cap Enhanced Mix:  https://www.youtube.com/watch?v=cgf4S5fw1qM

The same sort of treatment was given to many Dragon Quest songs, with later iterations of the same tracks.  All made longer, on top of enhanced quality.

But what is the ideal length for you? Or conversely, what could be done for short loops to make them not as repetitive?