If you were put in charge of the whole of the London Underground, what would be the first thing you'd try and change or improve, and why?
I think a really good idea would be an Outer Circle line. Something that links the ends of the lines - ideally all of them, thus forming a Circle. It would be particularly easy to link Cockfosters, High Barnet, Edgware, Stanmore, and Harrow & Wealdstone, for example, as they're all quite close geographically. It would save un-necessary trips into and out of Zone 1 to change lines, hopefully cutting journey times and congestion.
Also, there are some places where two Tube lines cross without an interchange - such as the Met & Bakerloo at Kenton, the Hammersmith and City & Central at Shepherds Bush, the Piccadilly & Central at Park Royal. Would save the need to leave & re-enter the network when changing between them.
These changes should also help Tube Challenging somewhat
I don't want arguments in this thread - you don't need to tell me why my ideas couldn't happen, or why they won't happen - they are just hopes of mine. Now your turn!