I agree with what you wrote above.
The issue of confiscation or freezing accounts is sometimes wrongly understood. Under capital restrictions, you also wouldn't get any goldbars or coins easily through an airport i.e. gold held privately would be of no advantage if it had to be moved. 'Confiscation' wouldn't happen as such (if at all), but as a forced sale at a determined price, maybe even the market price at this point in time. So what you would do is simply take the money and buy the next best thing, e.g. palladium, platinum, silver, copper, or even houses or other types of hard assets to protect yourself against the currency criminals.
The biggest of all dangers is really capital restrictions. In 1-2 years, when no one will want to live in the UK anymore (especially no rich Arabs atc.), they might revert to them. If you intend to leave as well, then there is a real danger with UK only companies/banks, maybe Channel Islands will be slightly better.