I think it would be nice to get a hole route because these parts of routes aren´t this nice (to be honest). Also it would be great if the AI could be more intense on the "Stammstrecke" from Donnersbergerbrücke to München Ost.
What about more S4 Services I think 115 Services is not too mich enough . Extension to Munich Ost will be okay but only the S3
Unfortunately extending the line from Hacker-brücke to Holzkirchen would've used too much memory. A better suggestion is a München S-Bahn DLC with the S8 to München Flughafen Terminal, S4 to Trudering, S7 to Kreuzstraße and S3 to Holzkirchen. All of these services would start/end at Hauptbahnhof. Then if you want, continue to Mammendorf using the München to Augsburg route. I don't know what would be the best way to cover the section between Hacker-brücke and Holzkirchen. Maybe an automatic route change in the Tunnel? Anyway, a München S-Bahn DLC would be more resource-friendly to console and PC users.
Only S-Bahn is okay, this makes sense even more than a S4 with 115 Services, which is not an primary route.