If they cast Solo correctly and stick to a serious story, A Han Solo stand-alone could be be really interesting. They need to stay away from the OT. The world is very aware of Han Solo and who he is as a person. We don’t need a bunch of name-checks or OT references. Something along the lines of the Brian Daley novels. Han Solo and Chewie long before we ever met them.
I’d go with Stars’ End and tweak it as necessary. Show us The Corporate Sector. Let us meet Jessa. That’s a perfect spot for a female lead. Nothing wrong with taking a break from The Empire, The Force, and The Sith for a few hours. I’d certainly welcome it.
Emma Stone in her natural blonde would make a great Jessa.
She’d probably make a better go of it than Chris Evans.