Hello and welcome to the RTA forums !

With detours, your trip will probably equate to over 4000 miles, or close to 250 miles per day. Where as you can divide that into shorter and longer days to suit, we wouldn't recommend doing over 500-550 miles in a single day. The average is doable, but it will be a trip that keeps you on the move when considering the slower pace through the parks and coast etc. What I would have considered doing is splitting your trip differently so that you don't feel your trip has finished in Tahoe when you have 3 hard days driving home ahead. I would be considering visiting Crater Lake on the way back from Tahoe, possibly via Lassen Volcanic NP and possibly the Columbia river Gorge and keep more to the coast on the way south.

Canary Wharf and the Piers are fun and vibrant in San Fran and if you want a real treat book yourselves a boat ticket to Alcatraz via the NP website.