“but needs individual negotiated overflight permissions.”
This is not really the case. There is a standing agreement with most of Europe dating back to 1980 which removes the need for individual permission in most cases. The Professional Footballers Association will not help, but the LAA might.
“it's a universal condition on the permit to fly that you can't overfly congested areas - weight's irrelevant.”
This information is out of date. The overfilght restriction has been lifted, but there are some caveats. One is a weight restriction of 1500kg, so no in a 2500kg aircraft you would be technically braking the rule…
Rod1