Modern Human | Free
Word of caution: most humans in the year 2185 have their cognitive abilities damaged beyond repair by virtue of smartphones and hamburger-only diet.
Hillbilly | 500 credits
Human beings of the past require the use of highly expensive time machines to obtain, but it is well worth it: back then people could think in ways that the today’s humans can not even begin to comprehend.
Hillbilles can either buy scrap or collect the remains of destroyed structures (both alien and their own). They can then jerry-rig various simple things out of scrap, here are just some examples of what could be implemented:
Ladders, very helpful for rooms like the Karith elevator room.
Rope slides, can help crossing chasms, but are one-way.
Planks and bridges to cross small to medium sized gaps.
Carts which can be loaded with grenades, weapons, ammo and medkits.
Backpacks which can hold extra ammo for non-energy weapons.
Hillbillies also have a chance to duct tape structures which are about to explode back together. Duct-taped structures remain partially operational and will not detract from the BP limit, but have less health and deconstructing them does not recover any build points.