I'd go for Aqua. Besides the fact that water pokemon kick *** I'd imagine there'd be other benefits too like:
1) More water = bigger tides, yes? Hence with more water we'd get more renewable energy from the tides
2) More water can absorb/dissolve more CO2 into the seas, reducing the amount of CO2 in the world overall and slowing down global warming
3) Things that are solid can conduct heat easier than gases or liquids. With an increased volume of water, the seas could absorb more solar heat and insulate the world better, once again slowing down global warming.
4) And of course, water would be more available over the world, helping to fight poverty and such
Just so you know I've done no research into this, I just thought these effects up on the fly, I don't know if it would work that way in reality I just imagine so basd on the basic science that I know.