As an idea for the Armour, you could model them off actual modern means of protection in the military. There would be 3 simple tiers of protection, Light, Medium, Heavy.
Light - MBSS
Protection to the front and back, and the ability to move at regular speeds.
Medium - CIRAS
Protection to the front, back, and sides. Minor reduction of mobility.
Heavy - Interceptor
All around protection, reduced mobility.
Obviously the blockland versions would look significantly different but, I'm just trying to give you some idea to base off in case you do decide to make Armour.