We also have an impatient two year old, so I waited in line at Dumbo (which was about 30 minutes) while my wife took our kid on the much shorter-line for the carousel 2-3 times and then passed her over the side of the line once I got less than 5 minutes from the front of the line.

Of course this requires 2 adults . . . but may be worth trying if you can time it right with another ride your son wants to go on around fantasy-land.