One of the things that friends and I have found is that although we use mumble to stay in touch and chat, we tend to play different games while doing this and having two of us in one game teamed up while 5 are in another tends to make things... confusing and annoying as we talk over each other. Only option at the moment is to switch channels and then we cant have general chat with each other.
Would it be possible to add a feature to mumble such as "guild chat" that allows sub groups? IE two of us are in warZ and join a guild chat sub group for it while the others are in GW2. Those in each sub group sound regular volume while other sub groups are lowered in volume (adjustable with a slider) so that although you can hear them, they are much lower and are easy to tune out or talk over as needed with out interrupting them (to them, you are lower in volume)?