Oh well I suppose I can do plot, if doing plot is required [grumpy]
Ross is a square peg in a round hole. Born into the gentry he despises many of his own class for their selfishness and vaunting sense of entitlement. Instead he is more comfortable with the local peasants, admiring their work ethic and envious of their simple, rustic lifestyle.
But he isn't 'one of them' he still feels a sense of responsibility toward them, like a father with his children. Essentially he is lonely soul. Caught between two very different worlds. He fought as an English officer in the American War of Independence but couldn't help but be inspired by the American's determination to escape the British rigid system of hierarchy and inherited status and authority.
Ross is a 'Romantic' in the original, literary sense of the word. Shunning the new learning and the new science of the 18th century and embracing the bounties of Nature and extolling a simpler, rural existence. The 'Romantic' poets and writers also had some rather disturbing ideas about the blurring of relationship boundaries between brother and sister and parents and children. Hints of incest are a very common theme running through out many Romantic novels and poems. Again this is very similar to Ross's relationship with Demelza. He starts off with vaguely paternal feelings towards her and sees her very much as a child and a servant. But slowly his feelings change and he begins to see her as a 'help meet' and lover.
He is an educated man but he chooses to get his hands dirty at the mine and prefers to do manual labour in the fields rather than drink port with his gentleman chums.
The two women in his life Elizabeth and Demelza perfectly symbolise this dichotomy in Ross's heart. Elizabeth as the cool, cultured 'angel in the house'. Demelza as the passionate, pagan 'child of the forest'.
Right. Can I go back to licking cake off his chest now [plaintive]