There are a few problems with your proposed solution, based on the facts as described in the opinion (and thus as alleged by Google's lawyers):
First, Google's architecture supposedly constantly moves data from place to place, so US law enforcement could spend considerable effort going to a court in France and convincing them they should hand over the data, only to hear, oops, while you were doing that we moved it to Canada. It also potentially splits data into many parts, requiring the US to go to several different courts. (Google also didn't even say which country or countries the data is stored in, though I suppose the US could probably subpoena that information.)
Second, Google says that the only system they have for giving data to law enforcement requires going through employees in the US, regardless of where the servers to be accessed are located. Makes sense, since their architecture is location-agnostic by default, and handling law enforcement requests is a specialized job. But a decision from a foreign court is not binding on those employees! US law enforcement would have to try to get the country hosting the data to go and physically seize Google's servers, and manually search through their hard drives. Admittedly, they'd probably only have to pull a stunt like that once before Google decided to get more cooperative, but it's still a messy situation.
FWIW, I agree with your concerns about foreign data privacy laws, but the solution can't be to effectively make certain data immune to court-ordered access of any kind. (Well, at any rate, such a solution would be contrary to political orthodoxy even in the EU, though cypherpunk types might be happy with it - a category I count myself in to some extent. :) Maybe the US needs to pass laws explicitly addressing this situation, but considering the current political situation, I wouldn't expect that to happen anytime soon…