Really nice. It felt really polished and the powerups for both factions is really cool. I also thought the fact that enemies went for health kits was an interesting touch, since you didn't always know if there would be a healthkit somewhere. I also really liked the stylisation.
This might be me being a bit of a potato though, but I didn't really understand the whole combo thing. I mean I knew of it from the tutorial level, but I wasn't sure it did anything since the enemies seemed pretty hard to kill, so I basically only cubed all over people in the campaign.. The other (slight) gripe I have with the gameplay is the fact that it's relitively easy to get into a stun-lock from cubes. I suppose this is balanced a bit by the powerups, but it's a bit odd to like give up for 15 seconds until you can become a helicopter of doom.