For starters cokecan, you forget that in order to occupy MPA and get all those aeroplanes & forces in situ, they will have to overcome the British forces already there. In addition, with Dauntless on the way down, they'd better be quick to launch any sort of offensive, otherwise they will be taken out before they cross the mainland airfields boundary.
As for casualty rates, they'll have to attend the party first. Rest assured that as soon as we show our intent, they'll be to scuttling back to port to watch the next match in the
'Cruiser General Belgrano' football league!