I'm kind of in the same boat. No real indirect way home (from work), at least for a majority of the way.
Any way I slice it, I drive (or have to walk) through Tampa, for instance. Now, once past the main part of the city, there is a pretty decent more back way to go that is along a highway, but at least not the Interstate.
That said, you can still use a highway and stay relatively hidden if you're off the road, and just shadowing the highway (if on foot) from the woods that are often to the side. They may be fenced and someone's property, but for the most part, you'd be unnoticed (and if you were, there'd be a fence between you, so that's something).
Tactically (and just for my own comfort), I'd be sleeping during the hotter part of the day, hidden away in some wooded and shaded area...and traveling more open areas mostly at dark (and on the side of the road facing oncoming traffic), where I could more easily spot a car coming before they ever see me. Along most highways, you could simply drop and lay down and become invisible to traffic anyhow. (as long as you drop before they see you).