It's also to be remembered that Beeching apparently commissioned the MGR system which still to this day is one of the backbones of the rail freight industry.
One thing to note though even though the commissioning of the MGR system may be attributed to Beeching, it was actually G F Fiennes who came up with the idea of the MGR, not forgetting also was partially responsible for the introduction of the Deltics.
The books he wrote are quite informative and interesting to read.
As to extra 91s not being ordered, that was simply down to the funding not being available otherwise BR would have introduced the InterCity 250 to operate on the West Coast Main Line however because of the limited funding,
the procurement of the Class 365, Class 465 and Class 466 EMU Networker stock was taken forward instead of these.
What would have been nice would be if BR had the funding available which would have meant both West and East Coast Main Lines would have 91s since the Class 93 got cancelled.
Onto Electrification, it's a shame that as the wires were going up they didn't wire up as much as they could have done ie:
Unknown
Sheffield to Liverpool Lime Street
Peterborough to Birmingham via Leicester
Sheffield to Bristol via Birmingham
MML
Bedford to Doncaster via Sheffield and Derby
Sheffield to Wakefield Westgate
Kettering to Loughborough via Corby
Sheffield to Grantham via Langley Mill and Nottingham
ECML
Ely to Norwich
Ely to Peterborough
Peterborough to Doncaster via Lincoln
Cambridge to Stowmarket via Bury St Edmunds
Ely to Kennet
Leeds to York via the 3 routes of Harrogate, Garforth and Church Fenton
GEML
Norwich to Great Yarmouth via Acle and Reedham
Lowestoft to Norwich and Ipswich
WCML
Preston to Blackpool
Lancaster to Carlisle via Barrow -in- Furness
Lancaster to Windermere
Leeds to Preston via Bradford Interchange
I agree with TBTC's valid point of small fleets though as well, this is something that shouldn't have happened.
If the above routes got electrified then just maybe FTPE would have gone with a smaller order of 185s to operate the remaining diesel routes and gone with AC versions of 444s for the other electrified routes.