@Newjez much of what you say has merit and in theory would all be great. i only have a point on a couple of yours.
The flight restrictions while they sound great i think it would have to be in countries of a few thousand cases not 100. We have already lost BMI, Thomas cook and nearly flybe in the last year. hitting the profits of airlines any more could see many more airlines collapse and the cost of air travel would sky rocket in the future [ i do understand that peoples health is more important etc but i really think it would be a last resort by the government].
Similar with the full pay etc as although it would be very harsh for someone to be losing out on money by having this virus. Companies still need to make money and may not be able to do so if it became a full blown epidemic in the UK and say half the workforce was off. Again companies could go out of business paying staff full pay for work that is not getting down etc.
Like i said in principle of the ideas are good but they are not practical unless as a last resort.