Even at its smallest, this new ship is nearly the length of the space station Deep Space 9 (1452 meters), and falls a little short of the Argus Array (2400 meters).
In my mind, the Enterprise is 300m long. The new ship is no bigger than the Excelsior. That is all.
The Abramsprise is 725 meters and that is coming from ILM ... that is a kind of BS given that it was designed to be something over 3000 ft long according to John Eaves. Either way, that ship is at least 2.5 times the size of Enterprise true.