Yes, I’ve had the (unfortunate) experience of visiting that station a number of times. At least the Munich station has a great biergarten across the street.
I’ve been to Hauptbahnhof Frankfurt more than a few times. I was stationed in Neckarsulm, nearer to Stuttgart, even nearer Heilbronn. I prefer Stuttgart to Frankfurt and Heilbronn to either of them, but Heidelberg exceeds them all.