AJ, I gotta take my hat off to you. Very good post, and covered everything that Ive been trying to post for 3 days without swearing

Just to add a bit more to it, I think the biggest issue you have here Paul is that your aiming to high with your designs, your trying to fit the best of everything into a design, without fully understanding each aspect.

You need to occasionally step back and say Hey, why havent I see a real robot with Etek drive, a massive pneumatic hammer and hardox armour? The reason why? Because it cannot be done within the weight limit.

Since youve asked for honest help, Ive draft a set of stats for Knocking Out for you, a set that I believe will easily make it into the weight limit and is still a reasonably competitive design.

Name: Knocking Out
Size (LxWxH): 600 x 600 x 300
Weight: 100KG
Speed: 15MPH
GC: 0mm at the skirts, 10mm under the robot
Drive: 2 x S28-400 Magmotors @ 24v, geared 8:1 onto 4 urethane (Volcalon) coated wheels in a 4WD configuration.
Weapon: The weapon is a Terrorhurtz style axe with a 270 degree swing, via a rack and pinion mechanism. The system uses a 80mm bore, 100mm stroke ram with a working pressure of 250psi (17 BAR), creating 860KG of force @ the ram, the system also has a 2L buffer tank to ensure a fast hammering action. The system is supplied by a 2KG CO2 tank capable of 45 shots @ 250PSI with the remainder shots at reducing pressure.
Chassis/Armour: 4mm Hardox front, sides and back, 4mm titanium top and base plate.
Batteries: 3 x 24v 3600Mah NiCD pack (20 cell packs) producing 24v @ 10.8Amp/Hours
Special Notes: Selfrights via weapon. Shaped like Beta (truncated pyramid). 4 x 3.2mm Hardox 450 skirts which are held on via a bolted rubber hinge.

Id have to CAD it to check that it is 100% in the weight limit, but just making some assumptions of weights it looks fairly close.