First-time Seattle → San Francisco road trip — does this itinerary work?

Hey everyone! Planning my first Seattle to San Francisco coastal road trip with the family and would love some feedback before we commit. Here's what we've got:

The route (6 driving days):

1. Seattle → Cannon Beach (stops: Astoria, Astoria Column)
2. Cannon Beach → Newport (stops: Tillamook Creamery, Cape Perpetua, Depoe Bay)
3. Newport → Coos Bay (stops: Thor's Well, Heceta Head Lighthouse, Sea Lion Caves, Oregon Dunes)
4. Coos Bay → Crescent City (stops: Bandon Face Rock, Samuel H. Boardman Natural Bridges, Harris Beach)
5. Crescent City → Mendocino (stops: Jedediah Smith Redwoods, Avenue of the Giants, join PCH at Leggett)
6. Mendocino → San Francisco (stops: Point Arena Lighthouse, Bodega Bay, Point Reyes, Muir Woods) 7–8. Two full days exploring San Francisco

My questions:

1. Are the drive times realistic? We're aiming for no more than 4 hours of driving per day
2. Are the stops well-balanced or are we still cramming too much in?
3. Any hidden gems along this route we'd be crazy to miss?
4. Any practical tips — gas stops, booking ahead, things that catch first-timers off guard on US-101/PCH?

Thank you!!