Planning a US road trip with kids

My sister is taking the plunge and heading out on a US road trip later this year with her 1 year old. She was asking my advice on whether she should play it safe and book one hotel to be their base from which to explore or do it proper road trip styleee.
Having done 2 big road trips with my eldest daughter Daisy in the US (the first one at 1 year and the second just over 2 years and me 5 months pregnant) I would say go for it!

• Allow for jetlag and mayhem after a long flight.  Don't immediately set out on a long car journey, perhaps stay in your first location for 3 nights
• Book most of your accommodation in advance, particularly if you require a travel cot.  Where I have travelled in US, all the hotels had cots/cribs on request so we didn't bring our own
• Try and pack light. If you are bringing in a baby, stroller, luggage etc every 3 nights to a new hotel you don't want to overburden yourselves.  You also need to make sure you have enough room for all that US outlet mall shopping!
• For older kids hire a car with in built DVD player or bring a portable one - it was a lifesaver for us on long car trips!
• Use child travel websites to find the best kind of itineraries for you.  Whilst the US has amazing national parks etc, the reality for us with 2 small kids is that cities are actually better and we'll save the outdoor stuff for when they're older
• Mix it up with your accommodation.  We stayed in some super cool inner city boutique hotels and then in the more random locations chose Courtyard Marriotts which were always clean, had kitchenettes and laundry facilities