@Zilla1
Yes, you are right, the graph is critical care not deaths (it is from the Imperial study) but the deaths will follow pretty much the same shape, just with smaller numbers.
@StealthPolarBear No, you are right too - I wasn't clear there. The highest peak would be unmitigated, then less strict restrictions and then the lowest would be a strict lockdown. And the nearest (quickest) peak would be strict lockdown, probably followed by letting it run, followed by weak restrictions.
I think the Government are trying to navigate a path here (that may colloquially known as "having your cake and eating it".
Letting it run would have least economic impact but by far the largest number of deaths. Obviously large numbers of deaths will themselves have some economic impact, and morally our Government eventually decided they couldn't justify the number of deaths.
A strict lockdown would have the most economic impact, but would have fewest deaths. The Government are not willing (currently) to take this action.
And then there are middle paths - which the government are trying to take, where you keep the number of deaths as low as you can whilst enabling as much economic action to continue as possible. Which for the UK means trying to make sure we have enough capacity for people who get ill, thus limiting the number of deaths. The problem with this strategy is it is inevitably going to be the slowest strategy - so overall you get a high number of deaths and a high economic impact, but not the catastrophe that either of the other routes lead to.
That is my understanding, anyway.