Some more crayonista stuff.

The line planned from the new Stoke Newington junction to New
Southgate... instead of
(Seven Sisters, Wood Green) or
(Seven Sisters, Turnpike Lane, Alexandra Palace) how about
(Harringay Green Lanes, Crouch End Broadway, Muswell Hill Broadway)
instead. In distance terms it would be marginally longer, but it serves
a lot more places that are very poorly served at the moment. If
interchange with the Seven Sisters Overground is essential, add a pair
of platforms at Stoke Newington immediately south of the junction.

It would miss out on interchange with the Picc and Vic, but I don't see
that as a major problem because the line largely replicates the Vic
anyway. Alternatively, run it from Dalston via (Finsbury Park, Crouch
Hill, Crouch End Broadway, Muswell Hill Broadway) and possibly give the
Seven Sisters Overground line a Stoke Newington interchange with the
Tottenham Hale Crossrail branch. But that would all be dearer, I think.