My thoughts for DF:

 

Second plan is better than first. 

 

If you really don't plan on gambling all your trip money away, you can sometimes get a really good room in Vegas really cheap at one of the casinos.

 

Grand Canyon is awesome.  If you speak German as well as you speak English, you should be able to communicate with all the other tourists there.

 

San Diego is one America's finest cities, but you may want to get there in the afternoon.  There's often a marine layer of fog over the coast in the morning.  Also, your drive up Highway 1 could be a foggy affair, so check your weather.  And for God's sake, take your time.  Nothing worse than being in a hurry in your rental mustang while trapped behind a bus on the 2 lane stretches.

 

San Francisco has a Chinatown, a Japantown, and might even have a Koreatown by now, so you're in luck.  If you're headed toward Seal Rocks or Golden Gate park, you may want to swing by Clement Street between 5th and California Streets to get your Euro voyeur vibe on.  Resist the temptation to drive up and down Van Ness just because of the Dutch name. Stay out of the Haight district - potheads trying to make money off folks embracing their inner pothead.  Nothing you can't get at home.

 

Skip a tour of Florida and stay in the Jax area.  If you like warm water, no need to go further south than Flagler Beach.  And as you know, Jax is a fun town.

 

Hope it's a fun one.

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