OK, I'll give up on the sneaky stuff! Hoof, that's a great shot of your sidecar and it's got me thinking again. I believe it would be entirely legal and not open to argument for you to have a headrest/fairing incorporated into the body work behind your helmet to fill that hole. I also think you could gain a small aerodynamic advantage by filling the space under your knees. It would be legal if it had a panel for your legs to rest on so that nobody could argue that your legs couldn't be seen from the sides. That same structure could come up between your legs, flush with the top of the nose cone, to form a very narrow top panel that stopped about mid thigh (so you were visible from above and had no risk of becoming entangled in bodywork) and helped tidy up the airflow and deflected some of the air that now hits your helmet. As for the deadman switch, SeaDoo make a really good switch with a stretchy lanyard for their PWC range that never
comes off accidentally, or maybe you could just use something as simple as a rubber band or an O ring to secure it, it would still release in an emergency but wouldn't fall off by itself.
As for the press on regardless attitude, once when I was racing my Formula Vee, the nose cone was removed at speed by the tyre of the car in front, the nose flipped up, hit my helmet and disappeared into the pack behind me. I kept going, had a great race and picked up the undamaged(!) nose on the slow down lap. At the National championships at Adelaide International Raceway in 1979 I did a sweep of the gauges on the main straight about half way through the race only to find the oil temp was maxxed out and the oil pressure well down (it was a very hot day). I considered stopping but quickly rejected that idea because the motor seemed happy enough (I always used good oil) and I'd driven half way across the country to be there. I finished 5th outright and best of the competitors who were there for the first time. As Winston Churchill liked to say, "Never surrender".