Additionally, you might prefer to leverage the low launch cost to use a different approach than JWST uses. Basically, Big Spitzer. Instead of a huge sunshade,

Additionally, you might prefer to leverage the low launch cost to use a different approach than JWST uses. Basically, Big Spitzer. Instead of a huge sunshade, use a telescope tube and a huge amount of liquid helium (even the relatively small amount in Spitzer lasted many years, and this is one instance where mass directly translates into time). Instead of big unfolding mirror, use a monolithic one. This would actually be technically superior to Webb (colder mirror and instruments than you can get with the typical Webb cryocooler, less starlight impacting the instruments as your telescope tube with baffles shields it better, less diffraction off the mirror segment interfaces) and ought to be potentially much simpler and cheaper. And you could afford to build more than one, allowing you to reduce risk aversion slightly and increase telescope time.