There are some good suggestions there, and some not good.
Registering and proof of vet care (cat MOT ) aren't a bad idea - perhaps along with compulsary RFI tagging. However confining to owners property and restriction on numbers are way off. Confining territorial animals like cats can be considered an act of cruelty, and some breeds can't cope with being in a restricted area very well at all.
Likewise restricting a number per household doesn't make a lot of sense - why shouldn't the owner of a nine bedroom mansion have more cats than I living in a single bedroom flat?