I disagree with the assesment of the Commissar. It depends on the situation.
For general purpose playing, yes the Cossack Captain riding on a KV-1 is a “broken” combination, and is much better than the Commissar.
If you are playing a defensive scenario and you are the defender, you might want the Commissar and some of the Chinese infantry for fodder. (My group plays historically-reasonable, if they probably had a similar unit, then you can play it on that country’s force). In combination with some of the Soviet Mortars and ZUKs, the Commissar can be highly effective by vastly increasing your successful hits.
The problem in most regular games is that you cannot afford 8 points of fodder for the Commissar. In fact, you can rarely afford 8 points that are not assigned to tanks.