Though Shannon Parry hit back with a patiently constructed try for Australia to draw level at 7-7, New Zealand always appeared in control to take their 24th straight victory.
Tui set up Niall Williams and then good ball movement saw Blyde cross for her 40th season series try. Nice inter-passing saw Shakira Baker cross for their fourth try to seal the victory.
New Zealand thus take back the World Series title from Australia, whom they headed by 16 points and lays a solid foundation for 2017-18, in which they will contest the Commonwealth Games, the World Series and RWC Sevens in San Francisco.
"I'm absolutely stoked. The ladies have been outstanding all season," says Black Ferns Sevens coach Allan Bunting.
Cup quarter-final: New Zealand 31 (Alena Saili 2, Kat Whata-Simpkins, Crystal Mayes, Michaela Blyde tries; Tyla Nathan-Wong 3 con) Fiji 7 HT: 17-0
Cup semifinal: New Zealand 21 (Michaela Blyde, Ruby Tui, Kat Whata tries; Tyla Nathan-Wong 3 con) France 7 HT: 14-0
Cup final: New Zealand 22 (Ruby Tui, Michaela Blyde, Niall Williams, Shakira Baker tries; Tyla Nathan-Wong con) Australia 7 (Shannon Parry try; Chloe Dalton con) HT: 12-7