"This isn't about making it the biggest; it's about making it the best," Semple said.
"We want to be as inclusive as possible and we want to give small country schools the chance to compete on the same level as big city schools."
The success of mixed six-a-side hockey in 2014 was a huge driver for the basketball and rugby expansion - the 16 mixed hockey teams that first year has since grown to 56.
Futsal was also introduced in 2016 - and the indoor football alternative has increased from 23 teams to 61 in that time.
The inclusion of kī-o-rahi is a nod to the growing number of kura attending the Aims Games.
"It means schools that might not be able to field a full rugby sevens squad, a football team or even have enough players for a basketball or netball squad won't be disadvantaged," Semple said.
"It's also reflective of the way traditional sports in New Zealand are having to evolve, so they can stay relevant. We'd like to think these changes are helping us stay ahead of the curve, taking us towards being an exemplar event."
Nearly 10,900 athletes attended this year's Aims Games in September, representing nearly 330 schools from around New Zealand and the Pacific.
The introduction of mountainbiking has been paved by the rock climbing's debut this year, the inclusion of BMX in 2016 and aided by Mountainbike Tauranga's recent success hosting the North Island secondary school championships at Summerhill Recreational Park in Welcome Bay.
The code allows multisport athletes another competitive element at the tournament.
"It's vital that kids at this age don't specialise too early - they need to try as many sports and pastimes as possible and develop allround skills and enjoyment," Semple said.
"That's a massive driver for us, to give our competitors as many options as possible and also expose them to other sports they may not have experienced before."
2019 codes: Badminton, Basketball (boys, girls and 3x3 mixed), BMX, Canoe Sport (sprint and slalom), Cheerleading, Cross Country, Football, Futsal, Golf, Gymnastics (including AeroDance), Hip Hop, Hockey, Indoor Bowls, Kī O Rahi, Mountain biking, Multisport, Netball, Rock climbing, Rugby (boys, girls and Rippa), Squash, Swimming, Table tennis, Tennis, Water polo, Yachting.