Okay SO for the On The Road plot I really like the idea of a young like just-out-of-highschool-aged girl, pretty straightedge, hitchhiking with truck drivers. Maybe she could be a runaway, tired of her conventional white-bread life, or maybe she has a fantasy of becoming an actress/musician and needs to get to California but she's never had to work a day in her life so she doesn't have a car or anything. Was Ivy-league bound and got fed up and dropped her whole life. Has made her way maybe a quarter of the way into her journey with nothing but bad, gross experiences and is about to just give up and go running back home when she runs into a truck driver / vagabond / whatever and they get to talking and she actually gets along with him and hitches a ride with him and then when he drops her off because he's at his stop, she's actually kinda sad that she has to leave and wants to stick around but doesn't wanna be even more of a burden so she takes off and then a few days later, by sheer chance, they meet again and that's when things really start to kick off. 

I'm so so sorry if this sounds nonsensical and unorderly. As soon as I saw your hitch-hiking suggestion, my mind took off and I kind of just regurgitated my thoughts, I assure you I do have a more organized thought process than what I have probably portrayed, haha. 

Obviously none of that at all is set in stone, and I don't want it to be too cutesy, it should still have edge to it and maybe some dark plot twists. It's just a baseline for an idea, please let me know what you think if you're interested :)