--Player model is larger while wearing this particular 'armor', 1.5x.15 - 2x2 squares.
--Player can construct / deconstruct from a larger range.
--Player can kill small biters just by stepping on them, (SMALL BITERS ONLY).
--Movement speed is reduced.
--Exoskeleton's armor/HP is higher than heavy armor, but lower than basic modular armor.
--Module Slot area is much larger than that of modular armors.
--Can't equip Energy Shields, Personal Lasers, Discharge Defenses, or Basic Exoskeletons.
--The player would still be able to use weapons and capsules while in the Exoskeleton.
An accompanying thought would be to have construction based modules as well as the combat based ones.
--Portable Furnaces (Burner & Electric)
--Storage Racks / Bins for extra inventory space.
--Portable Roboport (there's already a mod for it so why not?)
All pics were found by google image searching for 'lifter exoskeleton':