The hull has been redesigned with added armour. The whole frontal array is new, as you can see from the fact the entire thing is significantly raised compared to the Challenger 2. The drivers port of the Challenger 2 is a significantly smaller weak spot than the turret ring of the Abrams for example.
The final design will also feature a large block of armour for the lower front plate.
It is not underpowered compared to other NATO tanks of a similar era. It has the best NATO gun in service, it has brand new armour, state of the art optics etc…
The mobility is the only area it MAY lack in, and we aren’t even totally sure what the horsepower is yet as many sources state between 1200-1500hp.
If you believe the draintrain cannot handle a larger gun, then I’d like to point to the fact the Challenger 2 OES is pushing 75+ tonnes and remains reliable at that weight. This isn’t even considering the fact the Challenger 3 has upgraded suspension, transmission and engine compared to the Challenger 2 OES, at a lighter weight.
