I don't understand how using "fuck" a lot can be directly correlated to neuroticism. There are so many situations where it can be used that assigning the whole word to a signal for neuroticism seems like a misstep to me.
[1] http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3783449/figure/p...
You might be more prone towards agreeableness around others sharing your faith, but the more ensconced you are, the less likely you'll be open towards people with differences of opinion.
EDIT: Searching through the linked research paper, I couldn't find a single mention of "faith", "religion", or "religious", so I guess that was perhaps not considered.
EDIXx2: I think an interesting followup (to the research and possibly the tool) would be an attempt to discern how siloed away each person is and assigning a score to weight their other values. If you're in an echo chamber of everyone being #blessed, it's a bit different from seeing a wide range of opinions and activity. Even something simple like the mean distance of friends from the user's location, maybe with a foreign multiplier, I dunno.
EDITx3: Not even just distance, facebook has that about section as well. Obviously, many people have non-standard entries there, so some by-hand correction would need to be employed, but you could at least get a sense of someone's network variety.