Handley Page O/100 wings

[Graham Boak]

You are right that the V/1500 has equal span wings and the twins have smaller lower wings.
The V/1500's top wing is considerably higher above the fuselage, with upright struts from the fuselage - on the twins they come together on the wing.
On the V/1500 the engines sit slightly above the fuselage rather than at "shoulder" height, and have a more involved support structure. The twins have a strut that goes diagonally down from the engine to the lower wing root.
The V-1500 has four vertical tails.