Stay away! Don't you invade my home! Excellent!!!
That said, this game was considerably harder than Rome: Total War. Especially as the East or West Roman Empires as you must deal with civil unrest, new rebel factions, barbarian hordes sacking your cities, economic problems.... and thats only at the start of the campaign! This game takes the legendary Rome: Total War to new levels.
Rome: Total War Barbarian Invasion was much better than I could have predicted. A well earned 9.1!