The game needs modularity. I hope this will be implemented in transport fever.
A station should start from entrance, and then you should be able to add passanger terminal. cargo terminal, new platforms, platform extentions, bus/tram stop at the entrance, a pass through line, overhead bridge or similar.
Same goes with bridges. Aside from flexible bridges there should be modules with a straight bridge truss, both vertically and horisontally, or a shift button or something to keep that bridge straight! Then an option to let the game arch the bridge, thus bridges would look natural.
With all the mess player leaves on the terrain with unsuccessful experiments with quirky lane placement design, I say a ‘blueprint’ mode is a must. Adds realism too. An animation of a railroad being built following your blueprint would surely add to the game feeling.