The dream would be something like the Long Way series on Apple+ with Ewan McGregor and Charley Boorman (https://www.longway.tv/). Yeah, I know that's on bikes, but the idea is the same.
We have done a few longer trips on my Harley in USA: US North-East, the full US East Coast, Blue Ridge; and even more in Europe: full Atlantic Coast, Adriatic Coast, Eastern Europe, Middle Europe. However, now that the Missus is not that charmed sitting on the back of a motorbike for the larger part of the day anymore, doing this with the comfort of a car should be a great substitute! Now all I need is to convince her of the same!
So instead of heading out for more than a couple of weeks on our bike, something a bit further than just off-grid and a bit longer with a car would be amazing.
For now, I'll make do with weekend/day trips over here in the desert and the weeks in the summer on the bike (for a few hours in the morning and afternoon) and hope she'll catch the bug, so we can set sail for an adventure.
Oh and win the jack-pot, to finance it all!