My plan for the circle, district and hammersmith and city lines (feel
free to shoot it down) is based on the following:
1)existing frenquencys should be pretty much kept to.
2)olympia should have 6 trains an hour
3)lines shouldn't have lots of branches sprouting everywhere as
confusing
4)lines should be kept reasonably short, so as to try to reduce delay

here is a current off peak service diagram for the subsurface lines
(note values such as 7.5 have been rounded up)


ham----8---edg---16
| \
14 \
| \
oly hsk ls
| | |\
4 10 8 8 8
\ / \ / \
eb-6-tg-12--ec-18-gr-26-t-12-ae-20-w-16-b-12-u
/ /
6 12
| |
rich wim


I propose these services:

4tph olympia-tower hill-hammersmith
4tph wimbledon-tower hill-hammersmith
2tph wimbledon-high street ken
4tph wimbledon-edgware road-whitechapel
2tph wimbledon-edgware road-upminster
2tph olympia-edgware road-upminster
4tph ealing broadway-tower hill
2tph ealing broadway-tower hill-barking
2tph richmond-tower hill
2tph richmond-tower hill-whitechapel
2tph richmond-tower hill-barking
8tph edgware road-tower hill-upminster

to give: -


ham----8---edg---16
| \
16 \
| \
oly hsk ls
| | |\
6 10 8 8 8
\ / \ / \
eb-6-tg-12--ec-20-gr-28-t-14-ae-22-w-16-b-12-u
/ /
6 12
| |
rich wim

richmond/ealing broadway-barking line1 green
hammersmith-wimbledon/olympia line2 yellow
olympia/wimbledon-edgware road-upminster line3 pink
edgware road-upminster line4 bright green

This gives extra trains to olympia, that go further, and keep the
current service levels about the same, cept a 2tph increase from earl's
court to whitechapel (if this bit of line doesn't cope then
olympia-high street ken shuttles could replace half of the hammersmith
to olympia service) and a 2tph increase from high street ken to edgware
road, where the line should cope.
Termini would also have the same number of trains terminating, except
olympia and whitechapel, receiving an extra 2tph terminating.

line 1 and line 4 could be shown as one line, called the District Line
(for obvious reasons), though if the District was split on the diagram
then River line for line 1 and Bazalgette (bloke that made the sewage
system) line for line 4. Line 2 and 3 are hard to name, as what could
you call them without causing confusion? "Hammersmith, City and
Wimbledon line"? a bit of a mouthful, as is "Wimbledon and Barking"
tbh. One word names are nice and easy, maybe named after a person. any
ideas on what to call them?

Simon