I think at the end of the day it's up to what you're able to do. You could probably make a good mystery game in FPSC, just drop the guns - have NPCs who you can talk to. Also have items you can pick up - maybe try to solve a crime, scan the scene for clues and catch the culprit...alive.
Some games use elements like that, for example Call of Cthulhu: Dark Corners of the Earth...just ignoring the fact it has violence and gore in it, but the non-violent bits are good. It's not a crime solving game, but it comes in from that angle as you are investigating a scene.
Quote: "Location: Peterborough, UK"
And you live just up the road from me.