Feature A Better Way To Include London Underground & Overground Routes

I had a great idea how London underground routes could be included in future routes'

The Bakerloo line was a bit of failure when it first got released but over time DTG was very dedicated to eventually spend the time and hard work to fix the timetable for a realistic timetable. However with the success of the WCMLS the bakerloo line is incredibly fun to play however it is limited.

Nevertheless we can still can get a good 25-30 mins on the Bakerloo as it joins with mainline regional rail.
I had an idea when DTG decides to do another mainline rail route we could add in the addition London underground stock to prevent too much money spent on production and better marketing with mainline rail for a release so that we get a variety of routes on the next big release. The routes for example that share sections of track could be featured could be:

1. Operator - C2C - Fenchurch St - Grays/Southend Central
   (Drivable LU trains from Bromley-by-Bow - Barking/Upminster)
   (Possible LO trains for Romford - Upminster)
   (AI DLR Trains [Fenchurch St Approach - Limehouse] [Visible @ West Ham])
   
2. Operator - Chiltern Railways - Aylesbury/High Wycombe - Marylebone
   (Drivable LU trains from Amersham/Chesham/Uxbridge - Finchley Road)
   
3. Operator Greater Anglia - Liverpool St - Braintree
   (Drivable LU Trains from Liverpool St - Stratford)
   (AI DLR Trains at Stratford)
   
   
4. Operator Greater Anglia - Liverpool St - Hertford East & Stanstead Airport
   (Drivable LO trains from Liverpool St - Enfield Town & Cheshunt)
   
5. Operator Thameslink & Southern - London Bridge Services Via Norwood Junction
   (Drivable LO trains from West Croydon/Crystal Palace - Surrey Quays)
   
6. Operator Southern London Bridge - West Croydon via Tulse hill
   (Drivable LO trains from Peckham Rye - Queens Road Peckham or Surrey Quays)

If anyone else has any of variety that we could throw into together to make a realistic routes with local stopping services or freight would be great to add to this thread.

I strongly believe that this would will bring in the market of other train enthusiasts or casual players.