Lift and power is much more dependant on the profile (camber and airfoil), more than AR and even projected size often.
And higher AR can mean more power (total lift), because of less loss at the tips.
But lower AR which is a wider center chord typically, sometimes feel like it has more power at low speeds, as they will pull more "steadily".
Also remember, that it is most likely only the projected AR that is important.
So if a kite has a high "flat" AR, but more C shaped (like mentioned indirectly in an ealier post), it will most likely have a lower AR in reality.
Peter