There was little thought put into the euro because it's not an economic thing, it's a political thing.
I doubt that very much. The EU employs thousands of bureaucrats with qualifications coming out of their ears. These people believe that complicated plans can achieve everything.
It seems to me that too much thought was put into the euro. Without any fiscal constraints Greece might have hit trade deficit problems and that would have been bad for the euro. But nothing like as bad as what is happening now. What has happened instead is that banks and Western European governments have placed their faith in the fiscal responsibility that Greece signed up to when entering the euro, and so lent Greece billions. In a looser union they wouldn't have done so. Now we have a situation like if you owe the bank a million you're in trouble, if you owe the bank a billion the bank's in trouble. Western governments and banks are so indebted to Greece that they have no hope of getting their money back. The bailouts and questions of whether or not Greece will accept further fiscal responsibility both seem to excite the markets a lot but in reality can change little - Western banks and governments have lost a whole lot of money in doing this and Greece has to accept fiscal responsibility, bailout or no bailout, because it is now effectively bust.
Why has the West African Franc lasted so long when the euro is running into such problems? I see it as being because the euro is overengineered.