TF had a one flag "keep away" gametype. It was very fun. Flag starts in middle between forts. The idea was to get the flag and take to your own fort. The other team would then try to get in and get it back. Points for time holding the flag. Flag runner can't get into ammo rooms without exploding and sending flag back to center. As I remember, killing the flag runner sent the flag back to center (maybe not).
I enjoyed it more than DOM cause part of the strategy was where, in your fort, to hold the flag.
VG