Well really, during a pull, you shouldn't see any negative KC. I almost exclusively see mine at transient times, such as shifting points or when I drop from 100% to 0% throttle. I have had KC drop during a pull, but never go negative. Any Negative KC during the pull needs to be addressed as a more serious knock issue.
One of the real issues with tuning is there is no hard fast number for how much total timing is acceptable at certain RPM's. We assume the base timing map and timing advance map are acceptable, but with increasing boost maps and leaner fuel maps, there is no hard number to go on. Never mind the fact that if you look at the base advance map it looks nothing like a tuned base map looks.
I don't have any real hard figures to give you to start with for tuning your timing. Best bet might be to smooth the base timing map and flatten the advance map then adjust up until you feel comfortable, with an eye on knock sensor signals. If you have a WB02 you'll end up with alot better results since you can set your A/F targets more in stone and only worry about timing.