Greetinx!
I have looked at the pairings and guess that they are quite balanced, however the Liz/Borg Combo seems kinda overpowered: not decloakable cloakers, loads of colonists for ground battles, cubes with 150% damage, hissing ships over assimilated planets, ...
I'd suggest to exchange Liz with Fascist or Bird. What u think?
Otherwise I'd like to reserve this combo for my team...

Greets,
Chew