Leave all where they are. It is part of our history whether we like it or not.
Even the negative aspects of history are a form of enlightenment. Scorned though these figures may be today, in their lifetimes they loomed large on the stage, and without this nuance to provide the light and shadow, it is impossible to properly evaluate the past.
The only objective in covering up or erasing the past is to somehow prove the “new way” is unique, and being unique, there can be no going back. But every one of these “new ways” has been tried at some point in the past, and still shown to have failed every time. Any form of “command and control”, though it appears to be efficient and able to get things done initially, eventually ends up with way more control that is acceptable - prison camps for “re-education”, or mass graves deep in the woods somewhere, for the more intransigent who “fail” the re-education process. Various individual freedoms, largely taken for granted in the United States of America for the better part of a couple centuries, are either suppressed, or actively written out of the law, either legislatively, or by “selective” law enforcement and/or judicial review of legal decisions until the “right” interpretation is found.