Which space mission would you choose?

[Anomalocaris]

A single manned mission to mars can pay for all other items on that list combined 20 times over.   And the astronomical cost of a stunt mission like that would like lead to a reaction that would suppress funding for space exploration in general for the next 50 years, as witnessed by the premature end to the apollo program and subsequent drastic reduction in space exploration budget that has not recovered to this day.

So I would pick every item on that list except the first and last.