Probably the cheapest and best option is to build more wind and not care too much if it increases curtailment.
Yes, all the things mentioned should be looked into and done when it makes financial sense but "wasting wind" is much less a thing to worry about than "burning gas", and I'd rather waste wind than waste money.
Maybe not: "The Transport Secretary announced on 19 October 2022 that the Transport Bill which would have set up GBR would not go ahead in the current parliamentary session."
the franchising sysem won't be coming back
[0] - interestingly his "RailNatter" this Wednesday was titled "How to fix Britain's broken railways". I haven't watched it yet, but it will certainly feature some good insight: https://www.youtube.com/watch?v=CmKhVjw1xDA
Some of that is infrastructure (the cancellation of platform 15/16 at Piccadilly means the new Ordsall chord is basically useless, but they tried to use it anyway), I don't know enough about TPE to fairly attribute it, but with AWC it's franchise operation -- especially staff availability. Some of that is also government interference.
Why the left think a tory government would be any better running services than the train operators is anyones guess. When you dig down to it they seem to want more tax subsidies to big businesses (the ones who pay the £400 first class peak time returns on Manchester-London) and high income commuters (the ones with 50% discounts via season tickets who cause peak problems in the same way peak is a problem on the electric grid, and who typically earn far more than the average UK person who commutes via bus or van/car)
Fortunately the franchise system means many lines have significant competition, and you can choose based on journey time, price, and reliability.
Where privitisation does have its weakness is the financing of rolling stock.