This is one of the worst things to ever be proposed.
Quite apart from the fact that Newcastle / York to Birmingham is perfectly well-served (especially if York - Brum via Doncaster is going back hourly with XC), if you're doing pretty much any journey in that list of Newcastle - Derby, all of it can be done rapidly via St Pancras / Kings Cross and Thameslink down. You are not going to sit on a crumby (I suspect initially surplus 180) round the houses.
Then, there's the sheer stupidity of trying to thread a service into the North Downs which eventually will be 3tph won't it? At least between Reading and Guildford.
I would immediately assume that the smartest way of doing this would be to run down to Finsbury Park, round the Camden Road, over the North London, down West London and onto the Southern. This would remove needing to reverse at Redhill (which is congested), and trying to get into the mix with freight via Solihull and Oxford.
You would also have the added benefit of being able to add a call in at Finsbury Park in a sort of "out of London" way, giving you the option of cheaper tickets from the North East to there; you could stop at a major station like West Hampstead, as well as Shepherds Bush (Olympia is old hat), and somewhere like Balham.