Morrison said Westpac was a great ground for larger games, but did not work financially when the club was averaging crowds of only 7000 to 8000.
"A purpose-built football stadium has to be an attractive proposition for the Phoenix and although there are clearly a number of hurdles to be overcome, this is a proposal the Phoenix is keen to support," he said.
"The Phoenix's No1 stated objective from day one has been to make the club financially viable so as to leave a legacy for football in New Zealand. Any proposition that could make a material difference to the financial stability of the club has to be taken seriously."
Dr Morgan said a lower-cost stadium would enable the Phoenix to play more games in Wellington.
"We have to reinvent the game-day experience for fans and the start of that process is an arena fit for purpose, where the fans get up close and personal to the action with a ground tailored to the needs of a football audience," he said.
"We must follow the modern-day trend for football stadia internationally which shows the successful ones are intimate and designed to really amplify the fan experience.
"Only by building a 12,000 to 15,000-seat football-specific stadium with state-of-the-art technology will the fans turn up in sufficient numbers to safeguard the financial viability of the club long-term.
"This new arena promises this and while there is a lot more work to be done, we'd be crazy not to investigate the potential further."
The new stadium would include a children's play area and be structured to allow community groups to be part of the arena experience with food stalls and entertainment.
The Petone site was attractive because it was close to transport hubs - it has two adjacent train stations, and there are plans for a Tawa to Petone road link.
There were also a number of valuable partnerships situated nearby, including neighbouring Weltec, which offered potential education opportunities for the club.
The site was also near Capital Football's Memorial Park venue, which was an important component of the amateur game in the region.