"Secondly, there is actually hardly any difference between the cost of caesareans and planned natural birth if you take long and short term costs into account. (Only about £84.00 as estimated by NICE)."
But that's because a planned vaginal delivery now has a high chance of ending in a planned c/s or assisted delivery, which is where the costs accrue.
And the reason the emergency c/s rate is so high is because the vast majority of low risk women are giving birth in obstetric units, which have almost double the rate of emergency c/s than midwife led units.
High emergency c/s rates are also linked to staffing issues, namely a lack of one to one care, and a lack of consultant input after a labour starts to become complicated.
So surely it should be a priority for the NHS to spend whatever money they do have on bringing down emergency c/s rates (which would also significantly reduce maternal and neonatal mortality and morbidity) by:
a) increasing midwife numbers
b) improving access to birth centres and out of hospital birth
c) improving consultant cover in obstetric units
The average rate of unplanned c/s nationally is 14%. Some hospitals are as high as 20%, while others are as low as 13%. If rates were reduced (by spending money on doing the things I suggest above) to bring most hospitals in line with the national average, then planned c/s would begin to look like a very expensive option in comparison. In other words, it's only comparable because women planning vaginal births are so often getting suboptimal care which is resulting in high rates of complications. 
As for lobbying for increases in NHS funding for maternity services - well, yes! But if we are having to make decisions about how CURRENT funds are used, then I still hold that safety has to be prioritised, and that means increasing midwife numbers, even if it's at the cost of reducing access to c/s on maternal request and in the absence of a diagnosis of tokophobia.