Long Trip Considerations

We have probably taken 25 plus, 3K plus road trips. So these are our thoughts
1) Which will you enjoy more? Planning every night, or going where the wind blows you? Nothing wrong with either approach, folks are just different. We are where the wind blows us.
2) Anything you have every read about, like Yellowstone, Mount Rushmore, is you and 50,000 of your best friends. All good stuff to see but they are crowded . Something we don't like.
3) Very often it is the small stuff, that turns out to be the best.
4) campsites are like motels, there is always one somewhere, it maybe 75 miles further than you wanted, but you will find one
5) We are a big fan of KOA's, not because their campgrounds, are all that great.
but because if you have the KOA app, you can decide where you want to go that day, make a res online and have a site without all the worry of "where are we going to stay tonight.
6) Our in-laws, plan every detail, that would drive us crazy. On the other hand our go where the wind blows would drive them crazy. So I think figuring out what makes you happy in that way is a good first step in your planning

Don't fight the weather ! This will mean that arrival times, in hours and DAYS, need to be flexible.

Keep reminding yourselves that a long trip is just a series of shorter ones.

Is there a set timeframe, or just basically take as much time as needed?

I have mixed feeling about interstates. They're great time savers for getting to a destination, but no doubt little things along the way will get missed.

Generally I'm ok with missing the minutiae of a long drive, since my time is limited, I elect to spend it on my destination.

My recommendation is take some spare parts and do a thorough check on everything before heading out.

Worst part of a long trip I've had in years past was a broken spring and the repair shop pretending that there's no internet, taking four days to get a replacement in. Next trip I undertake that's more than 1000 miles, an extra spring and hangers will make the trip too, not that I expect to need them.

I assume your looking at next year or possibly farther out? Plan to stay off the interstate. Maybe head east and get on 395 north. Stattle? Why? Nothing there but more homeless and all the filth thst goes along with it. You could take 395 all the way to US2 east across the top of the country. Lots of wonderful things to see and do