Re: Designing the perfect Mecha or Giant Robot.
H'mm, for another take on a direct neural interface-operated "mecha", check out Dale Brown's "Day of the Cheetah" which features an advanced aircraft called the XF-34 Dreamstar.
For the mecha, I'd go with an Apache-style weapons-aiming system, so where you look is where the gun points, etc.
Also, MetalStorm and cold-launch technology would be useful for the missiles.
Plus, a holographic visor mounted HUD.