...or would it be preferable to treat people as external, manipulable objects?
There is no difference between these two modes.
Once you have "perceived" another as yourself, you will panic when they do something you wouldn't do. You will then attempt to manipulate them into being as yourself much as you might pull your hand away from a hot surface.
Perception is unachievable. Per - is a prefix meaning one for each. Peroxide, one oxygen for every hydrogen. Percent, one for every 100.
In this model, perception would mean something like one for each notion. That is the ability to see all aspects of something.
Perception is impossible because we are limited (not flawed) species.
Instead we have reception dependent images. We also have the limit that we are convinced of the fullness or completeness of our awareness with only a few inputs.
Our so called perception is rarely more than the memory triggering of common previous perceptions.
It is therefore important to begin with acknowledgment of fragmented awareness and to retrain our survival oriented habits partially toward perceiving through fewer layers of unconscious choices already made. Also accept that a full perception may involve many rather than few interfaces. Simplicity is a convenience not a law of the universe.
Atlas. Pay close attention. This is how you get your point across, sound smart, be informative, and still keep your friends.