Value of 'unicorns' and economic growth
The UK has had pretty poor economic growth for over a decade. If we'd continued growing at the pre-2008 rate, the economy would be £500bn bigger today which could mean lower taxes and more public investment.
One interesting measure is the value and number of 'unicorns'. The UK is middle of the pack but well behind the USA and China. Part of the reason is the availability of VC funding - which the UK needs to do much better at.