Limiting factor is power.
The major weak point in any of these concepts is being able to power it for any reasonable amount of time without all your payload being power systems.
That would be equally true of either a battle suit or a similar-sized robot. Once the problem of power is solved, the tech will probably diverge into battle suits and remotely-operated humanoid robots. The latter would be less vulnerable, and have more flexibility on shape and actuation.
And then, maybe....
GIANT ROBOTS!!
Chicks dig them, you know.