I think that sun roof design could actually work quite well, personally. Just make sure it’s supported with some columns somewhere to keep it a bit more physically accurate
I’d possibly add a supporting section either between the rails and incorporating the roof in part of the design to make sense with the support section or on this edge between the sunroof and the wall: .
With this supporting section you could use it as a base for what I’m guessing are the iron beam supports.
In terms of a supporting section and how to detail, I’d possibly do something like the following: a column with shallow arches between each basically
The design thus far looks amazing, and the industrial architecture suits a train station very well. Like others said I would add various columns. I would also add some kind of iconic hand clock. This could be done hanging from the ceiling or on a post or some other column.
Finally for the roof, I would add levels.
Ex. Like in this image the roof is built up in the center.