i now exclusively protect the kang....no matter what. i have my extend shields on kang as much as possible. i have found that as long as i focus on kang my win rate on cse has increased dramatically. i'm not saying i am a super player or have the best ship ever. i just simply protect the kang.
If your ship is worth a hoot you should be able to solo the Kang without any of the borg ships ever getting close enough to fire a shot. The opportunity to do this rarely occures because there are usually 4 other players that think they need to protect the Kang too.