It Will Be Even Bigger Than The Sea Wolf Class
If the SSN(X) is going to come with the armaments and features needed to edge out its competition, it needs a hull that is bigger than the ones featured by the Seal Wolf and the Virginia models. The former can carry 9,100 tons, while the latter has a capacity of 7,800 tons.
The Engine Might Rely On Two Types Of Fuel
As you can imagine, a vessel that big will need a lot of power. The new design should come with an engine that runs on both diesel-electric and nuclear power. However, there is still plenty of planning to be done.