BerkshireRails
On Moderation
This is very much a fantasy; however, how would you do it if it were to happen?
I would double-track the Redditch Branch, redo the quad track between Kings Norton & Barnet Green to be paired by use rather than by direction, build a tunnel between Kings Norton/Soho and Dudderston for Cross City and Chase Line services, with new deep level platforms. New turnback sidings at Dudderston and reuse of yhe Vauxhall Goods. Line speed would be 60mph, with ETCS L2, platforms would be built to 1.2m to have level boarding with the 730s and able to accommodate a 10 car 730/2.
Line renaming Kings Norton to Barnet Green,
Up Gloucester Slow->Up Gloucester Fast
Up Gloucester Fast->Down Gloucester Fast
Down Gloucester Fast->Up Gloucester Slow
Down Gloucester Slow->Down Gloucester Slow

Line renames Dudderston area,
Down Vauxhall Goods->Down Vauxhall
Up Vauxhall Goods->Down Crossrail
Down Vauxhall->Up Crossrail
Up Vauxhall->Up Vauxhall.

Service frequency,
4tph Chase Line (Wolverhampton to Walsall),
4tph Cross City Line (Bromsgrove to Litchfield Trent Valley),
4tph Cross City Line (Redditch to Four Oaks),
4tph Cross City Line (Longcross to Dudderston).
I would double-track the Redditch Branch, redo the quad track between Kings Norton & Barnet Green to be paired by use rather than by direction, build a tunnel between Kings Norton/Soho and Dudderston for Cross City and Chase Line services, with new deep level platforms. New turnback sidings at Dudderston and reuse of yhe Vauxhall Goods. Line speed would be 60mph, with ETCS L2, platforms would be built to 1.2m to have level boarding with the 730s and able to accommodate a 10 car 730/2.
Line renaming Kings Norton to Barnet Green,
Up Gloucester Slow->Up Gloucester Fast
Up Gloucester Fast->Down Gloucester Fast
Down Gloucester Fast->Up Gloucester Slow
Down Gloucester Slow->Down Gloucester Slow

Line renames Dudderston area,
Down Vauxhall Goods->Down Vauxhall
Up Vauxhall Goods->Down Crossrail
Down Vauxhall->Up Crossrail
Up Vauxhall->Up Vauxhall.

Service frequency,
4tph Chase Line (Wolverhampton to Walsall),
4tph Cross City Line (Bromsgrove to Litchfield Trent Valley),
4tph Cross City Line (Redditch to Four Oaks),
4tph Cross City Line (Longcross to Dudderston).