No one hot wires these cars anymore. Most car thieves wouldn't even know how to drive your car if it's got a manual transmission. If it's not a new honda civic, the odds of it being stolen by the average car thief are pretty low.
But, those aren't the guys that will be stealing your car out of your garage. The guys stealing it out of your garage will be using wheel dollies to put it on a rollback. Because the guys that actually steal classic cars nowadays know they can't start them up near the house (too loud), know they can't just drive them around without attracting attention, and know that guys have different methods of disabling their vehicles. They also know that they can't just sell them anywhere, because even the parts are relatively easy for people to identify because it's all unique. If a simple hidden kill switch won't stop them (like your neighborhood kid joy rider), no fancy brake locks or alarms are going to, because they're not stealing it for a joy ride. They're stealing it to put it in a shipping container at the port and they've been paid good money to do it.
There was a hot rod stolen out of SoCal a couple years back, the whole story was on the HAMB. It was parked immediately next to the bedroom window of the sleeping owner, and blocked in by other vehicles in the driveway. It was gone in the morning, the newer vehicles blocking it undisturbed. They'd put it on wheel dollies, rolled it out and down the driveway, and likely onto a rollback. Poof. You're not going to stop those guys with any of the above methods.