If you're talking about the book and not the political parties, hard to say. The one I enjoyed the less was the last one (blue). The first one (red) was strongly about survival whereas the second (green) was about sustainability. I enjoyed that a lot so let's say 1 and 2 ;)

Mmm, 3 was my least favourite too (though it does tie useful knots in a lot of the story) - I think 2 is my favourite with 1 a very very close second. I like a lot of the world-building in 2 which was less present in 1 in favour of the science :D