I used to try and defend but all it took was one rogue with Cloak of shadows and sprint to run past me. So I moved to running offense which has worked pretty well. I will get the flag, pop wolf form and run out. Between my alts killing and healing power I can usually make it across the map to help by the time im OOM or overwhelmed. At the start of the match I will usually thin out their offense so I can kill the flag carrier on the way back if possible.