None of Miles's arguments resonates with me, basically because one counterargument could erase the pragmatic relevance of his points in one fell swoop:

The vast majority of expected value is on changing policies where the incentives are not aligned with ours. Cases where the world would be destroyed no matter what happened, or cases where something is providing a helping hand - such as the incentives he suggests - don't change where our focus should be. Bostrom knows that, and focuses throughout on cases where more consequences derive from our actions. It's ok to mention when a helping hand is available, but it doesn't seem ok to argue that given a helping hand is available we should be less focused on the things that are separating us from a desirable future.