Ive been drawing a lot recently and have come to the realization that the Gigantic Armor is the best form for destruction. I cant think of a better design for warfare. High levels of strength, speed, durability (with extended range with shields), and weaponry. The only thing that I can think of to add to its already amazing line up of abilities is a tail with vibrational properties and even then it would be unnecessary with the vibrational swords turning into whips.

Can anyone think of something that would be as capable as a Gigantic Guyver?

The hyper smashers limit maneuverability. Not quite perfect.

I can point out weaknesses in the design and so forth. If you are talking about throughout the anime/manga/comics or whatever than he is far from it.