NLOTH live doesn't have the explosion-of-noise boom yet of the album version. If they can work on that song and actually make it blast off instead of just rumble along until the drums kick in like they do currently, then I'm up for it opening. As of now, it doesn't have that kick.
GOYB could work, if it were to follow a really interesting opening visual/audio barrage. Keep with the space theme, of the Zoobaby watching what the band and crowd is up to. Something other-worldly and futuristic. The countdown can follow and then straight into the riff, house lights turn on and the band is suddenly there.
Magnificent would be possible if they played it a little faster. Not metal speed, but just the slightest increase in tempo to get the song moving a bit. It's not quick enough to really have that POP good openers have. It has the perfect intro for an opener though, the whole loud note and synthy beeps/boops building up the tension. I wonder what ever happened to their intro they were planning on doing for Magnificent before the tour started?
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Would be kinda interesting if they had went that route. The band walking out unseen on to the dark stage. That eerie string music and droplet noises as the crowd waits in excitement. Then straight into the start of the song.