Surely a more typically British way of doing things would be to halve the budget and then somehow manage to muddle through with something that to everyone's surprise actually kind of works.
Things I think would be cheap and should feature in a truly British opening ceremony.
1) rain & mud
2) people talking loudly about the weather, and how there's no really bad sorts, only the wrong clothes (I suspect this is a less popular view in tornado & drought-ravaged countries)
3) tea, scones, beer and chicken tikka masala
4) randomised bureaucracy - maybe there would be pre-emptive feedback forms or something that the audience would have to wave in a synchronised manner.
6) the sea
7) whinging, sarcasm and comments that appear polite but have a dark inner meaning.
8) The class system
9) Britain in Bloom (an organisation which brings together most of 1-8)
How could this fail to be an opening ceremony discussed with excitement, confusion, suspicion and delighted disappointment for 999 days to come?