It seems to me that eliminating space-discounting is done for memetic, not genetic, reasons. And, as the triumph of individualistic nations over collectivist tribes shows, it outcompetes. "I trust strangers in the way a hunter-gatherer trusts his cousins" is not just a platitude for making people think you're moral, but also a good strategy for conquering the world.

Do values come from genes, and parameters from memes? The other way around? A mix? My guess is that most of our value drift will represent genetic strategies being replaced by memetic strategies, and so talking about values and parameters may not make a whole lot of sense.

It seems to me that time discounting is a heuristic to deal with death- if that issue gets resolved, then you don't need to discount as heavily. I'm not sure how a utility function would deal with memories, though- if I get to have an awesome experience at one point in my life, it seems like the earlier the better, as I can only remember the experience after I have it (I can anticipate it beforehand, but I imagine that'll be weaker). So my guess is immortals (or, at least, billion-year lifespan individuals) will have a weak preference for the present.