Assassin’s Creed: Syndicate - 10 Things It Must Learn From Brotherhood
9. An Overarching Villain Gives A Sense Of Progression
One of the best things about Brotherhood was that it felt like you were attempting to bring down the head of a Mafia gang - which, given the state of the Church at the time, may not be too far from the truth. Following the unusual decision not to kill Rodrigo at the end of AC2, there was always the looming threat of the Borgia forces recuperating and destroying everything you'd worked so hard to achieve.
Because of the way it was set up, it wasn't possible to just waltz into Rome, assassinate Cesare and Rodrigo and have done with it - they were practically untouchable when the city was fiercely protected and loyal to the Pope and his family. Instead, there was that sense of weakening them bit by bit, by getting rid of his allies and causing the populous to see them for who they truly were - it felt like you were moving forward with each assassination.
Only once their forces were weak enough was it possible to attack them directly - so there was a real sense of satisfaction and achievement when the time finally came. A similar setup in Syndicate would be a welcome nod to the roots of the series.