Both works develop themes of determinism, suggesting that their characters' lives are shaped by forces and/or circumstances beyond their control, leading them both to tragic outcomes. Significant differences, however, are found in the personalities of Willy Loman and Ethan Frome. Based on those differences, my sympathy lies with Ethan.
Willy worked hard, and at the end of his life, he regretted not having much of anything to show for his labor or to leave to his family. However, even in these final regrets, Willy's focus is on himself. It is always on himself. As a result, the entire family functions, to their detriment, in terms of their relationship to Willy. Willy can't see beyond his own needs, feelings, and frustrations. He never questions his own actions, instead blaming and lashing out at those who, he feels, have wronged him, betrayed him, or disappointed him. Biff takes the brunt of his father's criticism and scorn; in blaming Biff, of course, Willy does not have to deal with his own betrayal of his wife. When Willy's career falters and then fails, his fear, fury, and resentment are unleashed on Howard. It is true that Willy was experiencing a psychological meltdown at that time, but blaming others was his fallback position. He was argumentative and combative by nature. Willy's self-centered nature is finally seen in his suicide, but not in the sense that suicide itself is a selfish act; he was, after all, very ill emotionally. No, Willy's obsession with himself is found in one particular feeling he experienced before taking his own life. He hesitates momentarily in planning to commit suicide because others might think him a coward. The idea that his death will devastate Linda never enters his mind.
Ethan, in contrast to Willy, doesn't whine, complain or blame others for the circumstances of his life--not as a young man, nor as a tired, defeated old man of fifty-two. Ethan lives his life each day, taking what little comes to him, and bears it with strength and endurance. He asks for little and expects less. He simply does what he thinks he should do. When he dreams of a different life with Mattie, Ethan struggles to find a way to leave Zeena without leaving her destitute. Although feelings of sudden and intense hatred for Zeena flare in Ethan at one particular moment, born of his desperate frustration, he does not blame even her for destroying his life. Unlike Willy, Ethan does not plan his suicide attempt; he simply breaks, unable to endure the resumption of life without Mattie. Ethan emerges a more sympathetic figure than Willy Loman because of Ethan's basic decency.