[Bring_Back_Shantz]

I've done a similar trip on a motorbike twice, and there's lots to see and do.

Along the coast there's tons to do, the Sealion caverns are pretty cool (can't remember exatly where they are), you can go quading on sand dunes in Oregon (though with a knocked up wife that might be tough), and if you've got time Portland is a really cool city. Tons of great pubs/breweries, theatres, and some cool places to see live music (again, maybe not pregnant lady friendly though)

There's a really cool aerospace museum just outside of Portland and if you're at all into that stuff, it's really cool.
Not sure what it's called, but it's where the Spruce Goose is housed now so just google that and you'll probalby find it no problem.

As for the route you're taking you might want to consider going the other direction.
It's a lot slower going through Oregon etc, especially if you want to drive the west coast highway (which I highly recommend you do, especially if you're thinking of renting a car, and you can get a fun one). Coming up through Wyoming, Nevada, and Montana is a lot of straight flat freeway that you can make some serious miles on in a day in between stops.