OP I think your signs are hilarious and in no way rude. No one is entitled to shill on your doorstep, and you are more than entitled to express your feelings about solicitation.
You may not have to disconnect your door bell - maybe just put tape over it and a sign saying "Sorry broken / Out of Order"? Seems easier than having Mr. K fiddle with the wiring.

I don't know if this would be an ehell approved way to deal with some solicitors, but my exBFF had a huge dog that she would control only to the extent that she tolerated the person at the door. The racket the dogs put up when anyone knocked was often enough to deter some. If she answered and really didn't like what they were pushing, she acted like her dog (FWIW a very big Afghan with a
very big bark...but the heart of a chicken

) was difficult to control and it was in their best interest to back away off the porch slowly.

I can't afford a video camera but I have the poor person's "visitor I.D." - my family has a secret knock. Anyone who doesn't give it is ignored.

We and our neighbors also sometimes call each other and say things like "Heads up there's a kid coming your way with magazines" or "If you hear a knock in the next few minutes ignore it - there's some guy who wants his petition signed making the rounds" etc.