first step is a train wreck
You're going to work a full day and then drive a full day? That's a horribly bad idea and a way to wreck your trip before you even start. Getting on the road and covering some miles is one thing, but trying to drive 500 miles when you aren't even starting until late evening and are tired from the job is quite another. Assuming everything goes perfect and you get on the road right at 7, you wouldn't get to your hotel until 4am!
A common theme is that your travel time estimates are all way too low. In fact, they are even more optimistic than even Google suggests - and the only way to hit googles times is to drive without ever stopping for food, fuel, or slowing down for traffic.
The basic framework of your trip is ok, but that first day is simply not a good idea. If you aren't leaving until 7, I wouldn't plan to cover any more than 250-300 miles tops that first night.