I haven't seen Boardwalk Empire (it's next on my list), but I did see the other two. I would recommend you check out the British series 2004-2012 Hustle. If you enjoyed White Collar, I think you will enjoy this too. I actually started and finished White Collar after finishing Hustle, and White Collar felt like a huge downgrade. Hustle deals exclusively with long cons (normally 1 per episode for 6+ figure prize) and follows a specific team/group who become close friends over the course of the series (or by the start of the series). Also I have seen Boardwalk Empire recommended for someone who liked The Wire and Oz (maybe you should check those out too, they are both very good).