[DS 2] meandering about "Infantry on Steroids"

I was playing around with differences to individualize the Cotu nations and
came across these variations on "Infantry" and Mechas in my doodling:

Besides Line/Militia Infantry a nation/group might have -

Assault Infantry (AS) only - PHR in Cotu (using OOP figures, waiting for
Brigade Models figures)
Power Armor (PA) only - RH in Cotu (use NSL or ESU?)
Infantry Walkers (IW) only - NPC in Cotu (use NI and small BT PA as IW)
Combat Walkers (CW) only - not used in Cotu
AS + PA   only - not allocated in Cotu currently but possible
AS + IW  only  - IC (use IF and TBD as IW)
AS + CW  only - not used in Cotu
PA + IW  only - (these appear to be where the NAC, ESU, NSL and FSE
figures from GZG congregate)
PA + CW  only - not used in Cotu
IW + CW  only - not used in Cotu
PA + IW + CW  only - not used in Cotu
PA + IW + AS  only - LLAR in Cotu (using NAC figures)
PA + CW + AS  only - not used in Cotu
IW + CW + AS  only - not used in Cotu
All of these (AS + PA + IW + CW) - NEA in Cotu (use FSE for assault and
PA, plus BT for IW and CW)
None of these (Line + Militia only)  - UNSC?

Allowing that CW are to some degree background dependent and 'highly
optional' perhaps - what of these combinations make sense (in a strictly
SF tactical way)? Which seem 'unlikely' tactically?

Gracias,