This shows that you have not thought any of this through and just selfishly want more in your pocket.
Do you really want to live in a country that refuses to help those who need it? That’s a worrying growing selfish mentality in this country.
Besides that point, a good portion of our foreign aid budget is spent trying to fix things that we started! An example being Afghanistan, a country that we walked into for gain and then decided to walk right out of without fixing anything! So it is morally our duty to support these people given that we caused half their problems!
Cutting welfare will not have the impact that you foresee. Local services are already overwhelmed with the number of people dependent on them, cuts to this would make things inordinately worse. Unless of course by welfare you mean scrapping the triple lock, which is one thing that would make a huge difference.
The child benefit amount does not encourage people to have children, but supports those who are going to have children they can’t afford regardless. This actually means that it supports the children themselves. Again, i am saddened to live in a society that has become so ‘every man for himself’ that we do not want to support the most vulnerable in society.
Reviewing PiP in the way you suggest would likely cost more rather than save more. And by all claimants you are including people who have, say, lost their legs. Will an in person review help to see if they have grown back?
UK manufactured cars are hardly going to save a huge sum of money, and I’d be surprised if the cost of them was much different anyway!