For me the carryon and personal item are about the destination speed. In some international airports, I go from gate to car in 10 minutes. I have pre-check, global entry and their international variants like easy pass rtp in Germany. The reason I put the Dopp kit in my backpack lately is I seem to be winning the SSSSpecial screening on my return to the US. Once on the ticket but for the last four times in a row the third country national decides I am enough of an arse to warrant it. Thus, even with precheck and everything else the fluids have to come out.
I thought about putting my backpack inside my luggage as there is usually plenty of room. But I wasn't too keen on putting it next to all my clothes after it has been sitting in an airline seat footwell.
As far as carryon amounts go I agree. I can do a month out of my carryon fine. The departure and arrival loading and unloading of the passengers is the worst part of air travel. Even internationally people carryon more than they should -- if you can't put your bag in the overhead bin and get _completely_ out of the aisle in 5 seconds you brought too much or need to board with the feeble and elderly. The airlines also screwed this up by letting people with credit cards board early, as that means someone in the front row coach aisle is the first to get on, and holds up the line as they figure out how to get their huge bag, inspector gadget trenchcoat, umbrella, body-bag personal item, and stray cat into the overhead for 5 minutes. This is also the same person who will want to head toward the rear of the plane as we disembark to get the cello they stored in the back. Priority boarding generally works for those with frequent flier status as they have done it a few times and usually can get on and sit down.

Precheck is equally bad as now it seems to have made its way to many people for whatever reason. I am ready to go through security by the time I am at the security station. In front of me the passenger from before doesn't know what goes on and what goes off. They brought a tub of crisco with them and want to argue whether it is a solid, liquid, or gel. They took their shoes off but forget to take their keys out of their pocket.

I am all for inexperienced travelers flying -- but just don't cut them to the front of the line. I'll often fly on an itinerary where I go Europe->USA Hub->regional airport.

As far as being drugged to your destination: the three b's apply: booze, benedryl, and business class. Even without business class I can generally sleep most of the flight as long as I have a window seat. My 12 your flight from Munich to LA in the coach aisle seat, however, was torture. Between the big bottomed flight attendants and everyone needing to touch, grab, and shake every aisle seat as they walk to the bathroom -- I didn't sleep at all.

As far as bags go -- the Airporter from WaterField seems optimal -- but I still want something more like a backpack when I grab a bike to get somewhere. The best solution for the dangly straps I have found are the USWE "no more dancing monkey" straps: I just want to see them on something a little more useful/professional that retains the top "hanging loop" for j-hook attachment and all-black.