Flying Around
Some people said that the main operator for the mecha should be at the head.
To be honest, it was not completely true.
The earlier design did put the operator for the big mecha at the head, but then it gave some other troubles that they never expected. The head was quite a vulnerable place and might not be safe enough.
Thus, there were two types of design.
One with the control cabin at the head and one with the control cabin at the chest area.
Anyway, the size of the mecha itself was big enough to fit people inside either one. If it was the small sized ones, then there wouldn't be any of such debate.
But the big sized mechas were as tall as a building, so it wouldn't be strange for them to put more than one person inside.