Matt can half ass singing Showbiz and it'd still be a better closer than Starlight. He doesn't have to sing the super high notes, it's not like he sings the album version of the ending note of Survival live.
If they just swapped the two encores the set would be fine. Uprising and Starlight encore first and then the heavy as shit Unsustainable, PIB, Survival to close.
Overall, would love to see Starlight at least get rotated. If they can rotate Hysteria and New Born / Stockholm Syndrome they can rotate Starlight.