I'm okay with leaving it where it's at because 2, while good, didn't live up to the near-perfection of 1. It just captured New York and the look and music of the film so well, not to mention having so many of the original actors, and allowing them to flesh out some of the content from the book. I think 3 would have had the same problems as 2, where a lot of the film takes place outside of New York, so you'd have a tough time capturing that same cohesive experience of taking over a single city, like you did in the first game, to earn that final cutscene of all the top gangsters in the City coming to a meeting where you take your place at the head of the table.
They also deserve a lot of credit for how great the motion controls were done, not just on Wii, but even on PS3 as well. Grabbing someone with the shoulder buttons and swinging them around with the Sixaxis, or pulling them back and then throwing it forward to toss them off a rooftop was amazing. And also grabbing the shoulder buttons and pressing in the sticks to strangle someone, as the vibration slowly dissipates with their pulse... as sick as that sounds. Not only was the original version great, but we got even better re-releases on newer consoles with bonus content that made the experience even better. I think the only remaining evolution would be a Shadow of Mordor-like Nemesis system, where the five families continually grappled for control to retake rackets, or to carry out their own heists and compound assaults, which you could defend or even intervene.
