In Nixon’s time, “healing the nation” meant pardoning the rat. Because awful though Watergate was, Nixon had the good sense to resign and get the hell out of dodge and leave politics for good.
Trump has no shame, no sense of duty to party or country or anyone higher than himself. His crimes and abuses are bad enough as is and when fully exposed, will without question be worse.
This time, healing the nation means restoring justice.
If he tries to pardon himself, then SCOTUS must reject this theory since it will mean all future Presidents will be effectively above the Constitution and above the law.
If he resigns and has Pence pardon him, then at least history will forever record this shameful last act.
And he still won’t be immune from state law crimes and civil actions, The New York courts are getting into gear as we speak.