IMO, you're asking for a lot of trouble and a lot of expense you didn't plan on. There are going to be hundreds of miles of "no camping" in there.

There have been over the past few years a number of people posting similar plans. I have yet to see any of them come back to follow up on what happened.

I really don't see this as a good idea - the desert is unforgiving and deadly, and you'll have no way of carrying enough water through it. Walking on freeways is illegal and also probably asking for a truck to hit you. Hitchhiking is illegal. Walking across the open desert? oy. Do you understand what lightning, flash floods, rattlesnakes, dehydration, hyperthermia aka heat stroke, and cholla cactus can do to you? Understanding the risks before you go is paramount.

As mentioned in this thread already, the seasons that will be prime travel conditions for the various biomes you'll travel through are a big concern, and long layovers are likely.