RE: setting up pull-pull on a rudder
Slack should be avoided if at all possible even at maximum deflection because of the possibility of control surface flutter.
I agree that with small surfaces and slow speeds then flutter is unlikely but if you explore the envelope fully esp. in 3D style models then flutter might just bite one day.
My OMP YAK with a 120 AX would do climbing spins on full throttle both upright and inverted but I had to fix the slack in the elevator linkage to stop the whole tail fluttering. I was able to see it happen and get out of the flutter situation instantly so there was no damage.