What different challenges do eastern and western europeans face as they move toward a more unified europe?

The challenge between the unification of Europe represents a more cultural issue rather than a political or economic one.

Western Europe countries historically adopted the Latin language. The Western Roman Empire would collapse paving the way for the Middle Ages. Christianity is also the predominant religion in Western Europe.

Eastern Europe had a Greek influence that would later be replaced by a Byzantine one. Russians would later dominate the territory. Regarding religion, the Eastern Orthodox church is dominant throughout these countries.  

When people from both regions start understanding their differences is when the process of the unification of Europe will be taken to the next level.

silk

indigo  

rice

all the other answers are wrong