Other things that have fascinated me as I've alternated reading books about Firefly with theological/emerging church/spirituality texts are:
Thinking about 'Earth-that-was' (which had to be left behind) alongside inherited church or 'the-church-as-it-has-been' to quote John Pritchard (page 131 in 'The Life and Work of a Priest'.)
The way in which Whedon's version of the future incorporates ideas and images from so many different cultures and time periods alongside the 'ancient-future' nature of the emerging church.
River's words to Shepherd Book: 'Just keep on walking Preacher Man!' alongside Austin Farrer's image of the priest as a 'walking sacrament' (quoted in Pritchard, J, The Life and Work of a Priest, (London: SPCK, 2007) p.86.