Your comments are so blunt as to appear vitriolic - harsh criticism. If I may offer this observation, the problem is where you stop in your assessment of each person the pope has set forth for us.
Lincoln, whatever his personal feelings may or may not have been, ultimately freed the slaves. You stop by saying he was a racist, but he issued the Emancipation Proclamation.
MLK, whatever personal infidelities there may have been in his marriage, spearheaded the Civil Rights Movement. He was the right man at the right time, and so his legacy transcends any personal foibles between him and his wife.
Dorothy Day was at one time associated with the Communist Party, this is true. The problem is, you stop there. The last 50 years of her life, she was a devout Catholic and advocated something closer to Distributism, which is based on Catholic social teaching.
Each story is a story of redemption. The themes of mercy and forgiveness, and making much good come from that, run through each of their lives.