It's often a different decision with each individual boat but a few of the issues are:
Avoid locations in the path of a walkway where someone could step down and brush against the remote control.
Avoid locations where people will predictably sit down and lean back against the remote control.
High enough that the remote doesn't become submerged from the baskwash when stopping suddenly.
And, btw, no pressure washing.
Keep the boat cover termination in mind.
Double check the corresponding location inside the transom avoiding a conflict.
If you want convenient access to the remote control from the water than a location off to one side is better.