A couple of additional game modes could have added more value to the straightforward experience, especially online co-op, which would have done the game wonders. (glitchcat.com)
Playing and winning gives soft currency, XP and additional game mode currency. (deconstructoroffun.com)
I did tire of the «Fix the generator & open the gate» game mode towards the end of my second play session and feel this is something that could be addressed with additional game modes down the line. (otakugamers.uk)