What is your cuban tent?
I agree, I think the best use for bivy is steep country.
Finding a level spot to set up even a small tent can be a challenge.
I hate constantly sliding off my pad, keeps me awake far too much.
Hunting up around Stanley,Id. in some not too far from home places, [when I lived in Meridian,ID.] I planned on taking a small shovel and digging out some level spots, but never did.