The end problem is there is no incentive to engage.
I know TC's frustration., as you gain more skill and get known to the KOTH regulars...many will BnZ you above all others, avoid fighting you directly by not engaging. I don't consider a BnZ attack every 30 seconds or so, engaged.
So ... I've said so before, but they only way you change behavior is by changing incentives. The only way I can see for giving an incentive to kill, is by involving folk's K/D score with KOTH.
I posted before it would probably work well to play KOTH for 10 rounds or so, unless there is a 3-time winner-But if there is no winner after 10 round, the best K/D wins. Maybe with a bonus for being a wabbit, or having a single round win.
Plus it has the advantage of giving KOTH a set max time for completion. 10 rounds may not be the right number, but is just an example...But it would be nice to be able to estimate more accurately how long a KOTH would take, for CM's and players.