While trying to design a much smaller version of BattleDress (sorry but 3 m3 is just a bit too big for how I, and most Traveller artwork pictures BattleDress IMHO) I came upon a stumbling block.
Am I correct that in T20 one unit of vehicle volume, or vl for short, is equal to 10 litres or 0.01 cubic metres?
If that is the case then shouldn't a largish human be 10-15vl (100l-150l or 0.1m3-0.15m3)?
The quoted "100vl is about equal to an average human" can not be the human body volume , it must equate to a workstation/driverstation volume which includes seating, controls, headroom, wriggleroom etc.
A possible solution could be to assume the chassis to be around 100 to 150 vl and that the Marine inside "rides" it like a motor bike and thus requires only 11 vl (you may want to allow 15-20 for bigger Marines). This seems reasonable to me since the trooper is meant to be wearing the armour (very little wriggleroom).
I also propose that the AR be limited to a maximum of Str augmentation (I mean the Str bonus to damage). So if you want to be armoured like a tank then you will need a much larger battlesuit.
Next some sort of computer could be installed in order to run ECM, return fire (maybe even auto/evade if the suit is fitted with cruise-control

).
One final proposal is that the AC agility bonus of the armour is limited to the Dex bonus of the wearer.
I think a full Traveller's Aide could be written about BattleDress of different types across the range of TLs.
What do others think?