Do the signs mentioned upon a father's death—such as his face becoming illuminated and smiling, and the ease of his washing and funeral—indicate a good ending?

We ask Allah to forgive your father and grant him a spacious abode in His Paradise. What you have mentioned bodes well, and some of it is among the signs of a good ending. Dying on a Monday is the best day to die, for the Prophet, peace and blessings be upon him, passed away on that day. The illumination and whiteness of the deceased's face are signs of a good ending, as they indicate good tidings of Allah's pleasure and Paradise. As for feeling the funeral procession move, there is no evidence in it of the deceased's righteousness. And what some weak-minded people claim about the deceased being heavy or light in the bier, or flying, or running—that is a false claim.