So it seems a little strange to me that Medium armor gives the best protection.
I understand the direction Pavonis was going with it though
Light armor is for mobiity and extra abilities
Medium armor is for straight armor/HP
Heavy armor is for the weapon slot
Although from a lore perspective, it seems weird. It doesn't make sense that I move slower for carrying a single grenade, but I can wear a giant hulking suit of power armor with no mobility issues. Also the heavy weapons don't seem THAT useful in comparison to more armor, since most of your heavy-weapon damage will be handled by your technicals and grenadiers.
Wouldn't a mobility bonus/penalty make more sense? Like this
Light Armor: Mobility bonus, abilities
Medium Armor: No Mobility change, Decent armor/HP
Heavy Armor: Large mobility penalty. Amazing armor/HP and a heavy weapon slot.
It would make sense to put your tanks in the super heavy armor at that point
![Razz :P](./images/smilies/icon_razz.gif)