Regardless of the sensor, I know given my driveway grade, I'll need to raise the car every time I pull in. Unless raising is instantaneous, I think it would be a great addition to the Gravity software.
Question for @Osyris or @borski - Does Gravity have location-based ride height memory? When you raise the suspension at a particular place, does it ask to remember that setting and raise the location automatically the next time you're at that location?
This information in the Ride Control Systems section of the Gravity manual may be helpful to you.
I have a similar situation with some locations I plan to visit.