Someone moved my bike overnight and left a note taped to the seat - should I bother with a police report?

The scratching around the ignition cylinder is definitely something that needs proffesional inspection regardless of whether you file a police report or not. Even though the bike still fires up, forced entry attempts like the ones you described usually mean the cylinder pins or tumblers have been stressed or bent. If the perpetrator was trying to use a thin tool to bypass the lock, they likely impacted the internal components more than just the outer casing. You risk having a key that suddenly won't turn, or worse, a grinding noise that eventually leads to total cylinder failure. Nine times out of ten, once the metal is scored that deeply, the internal tolerances are compromised. Regarding the police, since the bike was moved, visibly damaged, and you received threatening notes, this crosses the line from a simple prank into property damage and attempted theft. You should report the incident to them. They might not recover the bike in the same hour, but the documentation of the incident establishes a paper trail in case that bike gets stolen later, which gives you leverage with your insurance company if you decide to file a claim for the damage. As for riding it or taking it to a shop, I'd strongly lean toward the shop first. While it’s running now, the engine and ignition are linked. If the thief accidentally bumped a nearby wire or caused a minor short while poking at the cylinder, the next thing you know the fuel injectors might start acting up or the electrical system could decide to give up entirely. You want a mechanic to at least inspect the wiring harness immediately surrounding the ignition before you put miles on it. They can verify that no shorts or damage were done to the starter solenoid or the ECU. If the shop confirms the cylinder itself is fine, but it's cosmetically ruined, you can decide whether you want to replace the cylinder or just live with the cosmetic damage. However, if the pins are bent, replacement is the only long-term solution becasue you can't really repair those internal pieces yourself.

This sounds frustrating, but treating it like an attempted theft makes the most sense for your peace of mind.

That note thing creeps me out more than the scratches honestly. Someone moved your whole bike 40 feet and left you a message, wich means they spent real time with it and wanted you to know it. I'd take pictures of everything before you ride it anywhere, including where it was originally parked and the note itself. My cousin had someone mess with his bike at night and the photos ended up mattering later when the same jerk came back. Did the note look handwritten or printed?

Had something similar happen to my old SV650 years back. Key got stiff in the cylinder after some idiot jammed a screwdriver in it, and it got worse fast. A locksmith rekeyed it for way less than the dealer wanted for a whole new lock set, so that's an option if the shop says the damage is minor. Also, the note angle makes me think it's someone who lives or works nearby. Might be worth asking around or checking if any neighbor has a camera pointed at that spot. Whoever it is knows where the bike lives.

I've worked the service counter at a bike shop for 11 years and the first thing I'd check isn't even the ignition. If they moved your bike 40 feet, they either defeated the steering lock or snapped it off, so look at the fork lock and the area around the triple clamp for pry marks. Steering locks are way easier to pop than ignitions and a lot of guys skip checking them. Also,OP, file the report online if your department allows it. Ours does and it takes ten minutes, no standing at a counter explaining a note to a cop who thinks it's funny.

The service counter guy is right about the steering lock, don't skip that check. Someone got into my old Nighthawk in an apartment lot and I completley missed that the lock tab on the triple was bent untill a week later when the bars wouldn't lock anymore. Cylinder looked untouched, so I figured I got lucky. Turns out they just went in the easy way. Also agree with the photos advice, my insurance adjuster asked for timestamped pics of everything and I only had half of them. One thing nobody's covered yet, do you have camera coverage on that street or a neighbor's doorbell facing where you park?