Give every character a free pair of toggles. Activating one of them will turn the other off:
- Extra threat: While this feat is active, you generate 10% more threat from all sources. This suppresses any sources of threat reduction you might have.
- Reduced threat: While this feat is active, you generate 10% less threat from all sources. This suppresses any sources of increased threat you might have.
There are several enhancements, destiny abilities, and items that increase or decrease threat, but you might not always want them active. This way you can turn them off without having to change your loadout.
Alternately, make every source of increased or reduced threat from enhancements and destinies into toggles.