Be careful of confusing manoevrability and agility. The former describes turn performance (min radius, max sustained turn rate etc), while agility describes how quickly it can change manoeuvre state, ie rate of change of AoA. Given this design is based on a legacy version, the large moments of inertia in pitch demand greater control power to achieve the agility required of modern fighter, especially in the post stall/high AoA regime. Also, as mentioned, better control power at higher AoA facilitates relaxed stability longitudinally, which in turn improves agility and possibly handling qualities, depending on how it is implemented through the flight control system.

In some fighters, one I can think of, differential use of canards can be used to increase directional control power as the pressure differential across the fuselage helps to pull the nose around. This is useful at high AoA where yaw, not roll, is predominant wrt aircraft axes when changing lift vector direction.