I'd do as you say, one bag each for the whole trip, with all of your things. It's not such a big deal to take two suitcases into a hotel each night, especially if you have ones that roll.

Since you admittedly over-pack, space is not an issue, and you seem to want the flexibility to pick and choose what to wear each day, I would also likely take a suitcase for each of you. Then, bring along a third empty suitcase, or large garbage bag, to keep in the car (trunk) to put smaller (hotel) bags of dirty laundry.

We travel a lot and I finally have a system. When we travel by car its great to have 1 change of clothes for each of you, toiletries for each, nightgown, robe, etc. all in one bag. If you arrive late at night or you spend more time at Yosemite waiting for old faithful,and are exhausted, its easy to just use the one bag. I also put a bathing suit for each, as indoor pools are common where we go, and it takes the kinks out of driving all day.
You can always go into the extra bags, if you need something. Also this last couple trips I learned that lots of hotels have a self washer dryer place. In Peru, the hotel for very little money will wash and return clothes, the next day. American hotels charge the earth for laundry if they do it. In Germany, I found a self serve laundromat, and had a great time at the internet cafe attached.
I usually have overpacked big time, and have gradually trimmed down, knowing I can launder on the trip. I pack a small tide and two or three fabric softener sheets.
Basic wardrobe anywhere in the world is t shirt, jeans, cashmere sweater, jacket, good walking shoes, tote bag big enough for shopping/camera. dressy black top for evening, with dressy cardigan or jacket and skirt or slacks, cute shoes and small handbag. I often buy something extra at the destination thats appropriate for the weather/area.
The other trick is everything has to go with everything else. One basic color with accessories. black with fuscia trim is my current for winter. black bag, etc. black shoes; otherwise on the last day you are left with blue slacks and a purple top or something.
My new theory--its easy and not expensive to buy extra light weight tops; or t shirts. Its a pain to buy jackets for cold weather (and expensive) or bathing suits. I also double check the weather with Weather underground and then call the hotel and ask--should I bring a jacket/raincoat, etc. Otherwise you end up in Washington DC with boots and a coat when everybody is out dancing in the unseasonable sunshine.

I hate dragging in all the bags every night and I hate repacking the car, so I would go for packing a bag for the first 3 travel days and another one for the destination. This is easier if the clothes for each part are definetly different - like more comfy clothes for travel days and dressier clothes for the destination.

When you're getting ready to head back home, you can re-pack the travel bag with your remaining clean outfits.

I would also put all shower stuff and toiletries into one bag of their own so they aren't in the wrong bag when you need them.

Since space is not an issue, I would probably bring a duffel of some sort to use as a laundry bag. If you can't do that and must keep all the clothes in the suitcase, then I've also used those travel space bags to keep the dirty socks and undies seperated from the clean stuff (because my DH's dirty socks need to be contained before they contaminate the whole suitcase!) - a big ziploc would also work for this.

We're back from the trip and this is what I finally did: 1 backpack that held a large ziploc bag of our toiletries, shampoos, etc. and my make-up bag. DH had his briefcase with the laptop. We had assumed that all hotels/motels with internet service meant service in the room. Apparently some of them meant service in the lobby. This is a question I'll be asking in the future.

We also had 2 suitcase, 1 small one with most of my clothes and 1 large one with all of DH's clothes, my pj's and shoes for both of us. While on the trip, though, I ended up switching some items to one of the 2 suitcases depending on how long we would be at a particular hotel. This way, we ended up only carrying in one suitcase instead of two.

Are there any flight attendants (stewardesses) around --I have always wondered what they carry with them. I know that they carry a limited amount of luggage and take it all on board with them. What combinations of clothing do they find helpful
and do they have any tricks we could appreciate and use?
We can't all be ex schoolteachers.

Limited amount of luggage? And they take it ALL on board with them??

They only are allowed one small piece of luggage.

They wear uniforms. There is not a lot to pack. Maybe a jogging suit or something conservative and comfortable that can be worn if they need to go down to the lobby for a newspaper or for breakfast.

I have had friends who worked as flight attendants and from what they say, all they do is sleep at the hotel and get right back on the plane.

They do not spend days on the Riviera waiting for their next scheduled flight out.

Sometimes they do not even leave the airport between flights.

Rats--here I was hoping somebody was spending their time on the Riviera with just the right things in their luggage.
In that case Marie 26 is an expert!

I wish I were on the Riviera but I shouldn't complain. We travelled through Idaho and Nevada to San Francisco. Then we went up the coast (unfortunately not via the water) to Seattle. Then we came back home. I had never been to San Francisco before and absolutely loved it! It was, however, very expensive.