How does this sound for a summer roadtrip route, roughly 18 - 21 days in length?

In order:

1. U.S. Highway 2 from near Duluth, MN (my hometown) to Everett / Seattle, WA - all the way!

2. I-5 from Seattle to Portland (a 3-hour trip?)

3. OR 18 from Portland to Lincoln City.

4. Hwy 101 from Lincoln City to San Francisco

5. CA Highway 1 / I-5 from San Francisco to Los Angeles to San Diego.

6. I-8 and I-10 from San Diego to El Paso to San Antonio.

7. I-35 from San Antonion back to Duluth.

Cities visited (in some depth) would be Seattle, Portland, San Francisco, L.A., San Diego, El Paso, Austin, and Kansas City.

Short day hikes and beach visits, plus stops at interesting attractions not far off the roads would also be included.

I certainly don't know if I'll be going on it, but it seems like a decent "itenerary".