First, there is no Amendment to the Constitution giving us the right to keep and bear Drones. The appropriate gov't body has always had the right, and the responsibility to protect the citizens of the US from harm regardless of the source. We have driver's licenses, doctor's licenses and even plumber's licenses. We have pilot's licenses. We have voter registration. We must be vetted to get thru airport security. We must have a passport to get back into the US. Nothing says we've done anything wrong, it's a way of reducing possibilities of us doing something wrong. You are going way over the top with your suggestion that all those personal identifiers (retinal scan, prints, etc.) could eventually be required.
Your missing a big point! you DON'T have to get a license for much of what you listed if you only do it privately or for free non professionally. For one this registration presumes that 1" off my back lawn is now public (not private) space(and not the relm of states authority). You don't need pilots license for ultralites, gliders, one man balloons, ect. No Plumbers license to fix your own or a neighbors sink, no medical license to do basic medical for you or others, No drivers license to build a Big Foot monster truck and run it recklessly on personal property. Now your right about about needing a passport but if ONLY drone owners needed a passport or had to submit to a search It would be a legal issue. And lastly voter registration is NOT universal law, many states like mine have tried but can't require people to register or even be required to show proof of citizenship! Another good example to compare is Ham Radio licenses, yes you need a license(as you should) for higher power levels but low levels require nothing and mid levels only require a simple license that is not data based in a way that the police can instantly respond. They would have to investigate and tie proof together to "reasonably believe" I may be a suspect, and that is part of "Due Process". This drone system drone lets presume guilt just because I'm a known drone pilot in the area.