Set to begin next year, the league will involve the Southern Premier League's top three teams mixing it with Mainland's top five.
The move was met with a positive reaction from Green Island coach Richard Kerr-Bell and Roslyn-Wakari coach Colin Thom.
Both agreed the league was conceptually a good idea and would help boost the game locally.
Their only major reservation came in whether it would lead to stacked teams.
With only three clubs qualifying for the league, it was natural the region's best players would want to play for one of those clubs.
It was something not lost on both coaches.
Thom said it would be of most concern to the mid-table clubs, as they risked losing their players if they did not qualify.
Kerr-Bell agreed and said Green Island had advocated for restricting transfers to the first two weeks of the season.
That would stop players transferring mid-season, something which would drastically weaken the non-qualifying clubs.
He also said it was important to ensure clubs had the chance to requalify each year.
However, the rest of the reaction was largely positive.
Both said the financial side looked reasonable and not too much more than the entry fee to the local competition.
They also both felt the travel was not an issue, with Thom saying the team had fun on its trips away, while Kerr-Bell felt it was simply a case of making it a priority.
Whether the top southern sides could compete with the Mainland ones was still a question.
Caversham has shown its ability to do so, although it has dominated the local competition in recent years.
However, both felt that side of it would be fine.
Kerr-Bell added that if the teams were not competitive straight away, it was a good way to learn and boost the standard so they could become so.
He emphasised the opportunity to play at a higher level as being the key factor as to why it was important.
''In the end, my perspective is that you've got to be playing at the highest level possible, or have your players playing at the highest level,'' he said.
''That helps coaching as well, if you're coaching at a higher level.
''I think that South Island competition will give us that higher level.''
Clubs would qualify for the league after one full round of the local competition.
The top three finishers would move into the South Island league, while the others would continue to play off among themselves.
Thom said ideally that would be two rounds of local competition.
However, he conceded that was difficult logistically without an all-weather pitch.
That would allow games to be played midweek and at weekends, without having a detrimental effect on the grounds' conditions.
