First, let me vent. Details of the journey will follow, when not blocked by freight trains using the tracks.
US rail needs numerous improvements. The lack of high-speed tracks is an ongoing national embarrassment. The long-standing, goofy fetish with "privatization" needs to end. No individual exploiter should get rich providing essential services like communication, highways, healthcare, or railroad tracks.
As a nation, we spend too much money on the firepower part of defense and not enough on the logistics or communications part of defense. The interstate highway system was helpful. We need the kind of defense infrastructure spending that will result in high-speed rail across the US. And broadband everywhere. More butter. Fewer guns.
And we need it now. Build Back Better.
Until we get military-scale funding for rail, we have Amtrak, and they're a lot of fun. Small. And slow. But. Absolutely wonderful. No Wi-Fi, but otherwise wonderful.
Here are the first few legs of journey from Red Ranger (docked in Charleston, SC) to see family in Santa Ana, CA, and Las Vegas, NV.
The first steps of our journey are to get out of the Cooper River Marina. See "The Palmetto" for how we used ride-sharing to get to the train station, a train to get the Union Station, DC, See "The Vehicle Recovery" for some details on using a rental car to recover our truck and drive to mom's in rural upstate New York.
Those first few steps were unique Red Ranger problems. What follows is more widely applicable to folks thinking about travel by train.
The Lakeshore Limited
We elected to board the Lakeshore Limited at the Albany/Rensselear station. It turned out that it also stopped in Schenectady, which would have been slightly more convenient for us. Amtrak's routing and scheduling options — while good — aren't the best at helping us understand our alternatives. It sure looked like the 19:00 from Albany was the only choice.
The Lakeshore departs ALB at about 19:00 and arrives the next morning in Chicago's Union Station. If you book the roomette, you get dinner, a place to sleep, and breakfast. Plus there's a shower. Bring your shower clogs.

The Lakeshore uses Viewliner cars. In these, the roomette starts like this with two facing seats. There's a little bit of space on the door side for a few pieces of luggage.
We bring a backpack (you can see CA's to their left) and an airplane-sized rolling bag. Those bags don't hiold a lot of stuff for a two week trip, but we plan to do laundry at our son's (in Santa Ana) and our daughter's (in Las Vegas)
Above CA's head you can see a vertical track. The upper bunk lowers on this track to rest on the horizontal bar with the lights and switches on it.
CA's backpack is resting on a step. The step is how one ascends to the upper bunk. We're mid-60's. Up until the COVID shutdowns, we went to rock gyms and climbed once a week. We're agile, so clambering up the steps to the upper berth was not even what we'd call challenging. Barely 5.5, if you know what I mean.
The two seats fold out flat to create the lower berth. No climbing required.
These new Viewliner cars are really posh. They have a little fold-down sink in the roomette. Pretty slick. The older Superliner cars are not this posh.
The car attendant will wrestle with the bed for you. Don't try it yourself. Flag them down when you want it shifted. You go hang out somewhere else for a few minutes. Then your roomette will be ready. CA likes to tip generously.
When the bed is folded down, the space between bed and door is on the order of 14″. You can barely turn around or get out of your clothes. It's tight. We took turns. CA hunkered in the lower bunk, while I got ready and climbed up. Then she could get ready down below.
It's noisy. The train bumps. It stops and starts. The conductors stop announcing the stops at 22:00 and resume at 06:30. Be warned, unless you live on a boat, it's noisy. If you live on a boat, it's nothing special.
The shower water on the Lakeshore Limited was cold, so I took a quick rinse.
The posh Viewliner cars have two outlets for your chargers. We use a 4-way USB port to charge two phones and two watches. If you leave this on the top step, it's possible to reach down from the top bunk to see what time it is.
Since it's an overnight there's no scenery. If you've never traveled by rail, it's worth doing this in daylight so you can see the back alleys and junk piles of America from the train. We were happy to make the trip almost entirely in the dark.
The Southwest Chief
The Southwest Chief is a completely different kind of train. It has an giant observation car. And the Superliner cars are two layers tall.

To fit two layers in the Superliner, means the roomette is a tiny bit smaller than on the Lakeshore Viewliner. One outlet. No fold-down sink. Less storage for our four pieces of baggage.
And. Less space in the top bunk. There isn't room to sit up. At all. You have to get oriented correctly as you climb up. If your head isn't by the pillow, you have to climb back down and climb up again, this time with year head and feet facing the correct way.
There's a set of belts to keep you from rolling out. "Lee cloths" is what we call them on the boat; since a train doesn't have a consistent windward-leeward heel, the name doesn't really apply.
We prefer to sleep with our feet forward. In case of a sudden stop, you don't hit your head.
Dining is by reserved time slots, on the half-hour. 18:00, 18:30, 19:00, etc. It's a three-course meal with numerous alternatives. Not that there are cloth napkins, but this isn't a posh restaurant. It's a train. Several steps above Denny's. But. A train. The meal were pleasant. There's a limited vegetarian selection.
The Southwest Chief's run takes about 41 hours. This translates to dinner, breakfast, lunch, dinner, and breakfast. There's just enough time to get tired of the vegetarian options and then the trip is over.

You do see quite a bit of Illinois before darkness. The prairie rumbles past in the darkness of the first night.
You wake up in eastern Colorado. The Colorado-New Mexico pass is a slow mountain climb. Then a descent to the desert southwest, the scenery slowly morphs into the spectacle of New Mexico during the daylight hours.

The Southwest Chief is not a "limited" it stops everywhere.
For example, Las Vegas. Las Vegas, New Mexico.
Yes, there's a Las Vegas, New Mexico, and it's big enough to have an Amtrak station.
I spent some time in the observation car, observing New Mexico.

It's spectacular.
Then, the sun sets. You'll pass through Arizona and may a corner of Nevada in darkness.
Sunrise is somewhere near Barstow.
Breakfast was 05:00 so they could get the kitchens cleaned up by the 09:00 arrival in Los Angeles Union Station.
I can safely say that arriving on the west coast rested, showered, and fed a cooked breakfast with plenty of coffee is a lot better than flying on an airplane and arriving cranky, hungry, and disoriented from trying to sleep in a tiny airplane seat.
I can also complain that there's no WiFi. Indeed, there's limited cell coverage. Amtrak and the various telecomm vendors need to make aggressive steps to fix this.
What you need in your roomette are your books and computers and what-not, plus two changes of clothes, bathroom kit, and a bag for dirty laundry. I'm looking at two pair of boxers, two T-shirts, two pair of socks, and a bag for dirty laundry. I think we could stage a beach bag or "packing cube" inside our roll-on suitcase. Drop the bulky suitcase down in the luggage rack. Keep just two backpacks and two packing cubes in the roomette.
Dreaming Big — And Fast
The train does take almost 10× as long as a flight: 43 hours vs. 4½ hrs. The track is 2,265 miles, the train averages over 55 MPH. They manage this by making some sections at 90 MPH. If the overall average was raised to 90 MPH, the trip drops to 25 hours.
I can imagine a Southwest Chief Limited with three stops and an average of 150 MPH on each of the 500 mile legs. (This is about the speed of the Shaghai-Beijing run.) 14 hours ORD to LAX! A boring overnight in a sleeper car or a looong day in a coach seat.
While I'm dreaming, I'd also like a high-speed train from Norfolk/Virginia Beach to DC. This is 195 miles; at 150 MPH, that's a brisk hour and change. Barely time to get settled with a book.
A version of the Capitol Limited could get the 780 miles to Chicago done in 6 hours. If the schedules meshed up, that would be a delightful day from boat to Chicago to catch the Southwest Chief. CO2 production for rail travel is about 1/10 of the production for air travel. See https://www.wired.com/story/cut-carbon-ditch-planes-take-trains/ and https://www.seat61.com/CO2flights.htm.