Is their anyway to lower the rev limiter further down than 3200rpm?   Kinda like another security feature for when/if I loan the truck to someone and don’t want them to be romping on it. 

As far as I know 3200 is the bottom. You could ask @Quadzilla Power if they would be willing add that option for say 2700 rev limiter which would be like old 12V.

Not really possible as the ecm is fueling if the quadzilla gives up control.  You could write a limiting table, but it wouldn't really work on multiple injectors

 

 

Use valet mode setting to limit power and set the tuner to lvl 1.   that will do exactly what you want it to do.