Top! As an Austrian, I suggest for instance the Viennese "Stammstrecke" (Wien Meidlung - Wien Floridsdorf), or the "Westbahn" (Wien - St. Pölten). But there are many more that have potential to be made for TSW3!
I agree with you however you only have a short section of the Schnellfahrstrecke Wien Linz Salzburg Westbahn. In reality it should be going and ending at Linz Hbf Passengers Freight Linz Verschiebebahnhof on the Eastern end freight train should be running Verschiebebahnhof Wien Kledering Passengers Wien Hbf. If that route were to be mean you should realize it's going to change the German routes meaning The Yards inside Wien Kledering Linz Vbf have DB Baureihe 204 G6 363 In return their home routes get an ÖBB Baureihe 1063 1064 2048 2070 shunting locomotives. Electric locomotives ÖBB Baureihe 1116 1216 1293 & 1014.
You mean the SFS Salzburg-Wien route. Oddly you can spawn the ÖBB Baureihe 1064 onto Bremen Oldenburg by working the Bremen Grölland Rbf and has enough tractive force to bring out the Sggmrss from there. 363 204 G6 will struggle with the Wien Kledering Hump