The Great Compromise solved the problem of representation because it included both equal representation and proportional representation. The large states got the House which was proportional representation and the small states got the Senate which was equal representation.
The modern development of today's world would have first made the routes safer. Today we have the safety of common things such as police officers, hospitals, e.t.c. Transportation of goods would have been easier, and it would have been easier to carry larger amounts of goods at one time.
hope this helps :)
