If the universe is likened to a detective story, a scientist pursues the question of how the deed was carried out. A good design on one world is a good design practically everywhere. Intelligent, technological species tend to be land creatures. Manipulative limbs don't develop underwater because they tend to impede swimming. Land animals tend to have four limbs, because symmetry and redundancy have survival value, and four limbs strike a good balance between enough limbs to be redundant and few enough to keep the animal structurally simple.
All higher creatures possess heads in which they carry their main sensory organs and their brain.
The sensory organs need to be as close to the brain as possible to speed up the flow of information. Imagine you had your eyes on your chest. Perhaps it isn't so mysterious after all that Homelanders look like Humans. Eljikorn's face looked like he was getting up the courage to ask a question that I might not regard as entirely tactful. I couldn't imagine what he had on his mind.