All depends what the plans are around parking. Something needs to be done and that remaining green space must look inviting to the designers.
But if they weren't planning on touching that, and it really was left green to be used as it is now, then what's the problem?
The stadium's basically an enhancement isn't it?
Similar in some ways to the Fraser Park situation in Lower Hutt - there's quite a large fenced off main pitch area with a stand there where Avalon premiers and other sides play. What's to stop Petone premiers playing in the new stadium with one stand open?
Great place for premier club football, rugby and rugby league finals too.