Forget false plates, they stick out like a vicar in a tutu. A black marker pen and a bottle of white spirits is all you need. Change an "L" to an "E" and wipe it off around the corner.
There's quite a line in stealing plates from cars to fit on matching makes and models. Non-trivial to spot unless you're happy to keep pulling over the victim, or reissue registrations.
They should target the drink drivers, increase the tax on fuel, stop the car tax and have a national fund for insurance. Everyone pays then. The more you drive, the more you pay.
I both like and dislike those options. Road tax allows you to tax differently efficient and inefficient cars. And by that I mean 99g of CO2/km gets free road tax, whereas your V8 Bentley would be paying £460pa. If you switched to pure fuel tax rather than that being a 0% vs 100% example, it'd end up being more like 20% vs 100%. Maybe that's okay. It'd directly discourage people from driving more miles, which would be no bad thing.
I'm not sure you should apply the same to insurance though, as then are you not subsidising poor drivers? I've always paid my tax/insurance/MOT and have a clean license and insurance. Under a national fund, would I end up paying the same as the 25 year old with 9 points on his license who has already been disqualified three times?