Life is what you make of it. So says my sagely friend Dan Urman.
So what, then, would make a good life for you? By this question, I don't mean simply your current living situation -- I'm asking about your entire life, a hypothetical best case scenario that is still realistic.
It's very difficult for me to answer this question (although the difficulty does seem to vary depending on how "realistic" is interpreted). I can think of two reasons for this. The first is pretty straightforward: I implicitly operate under the assumption of free will and non-determinism. Any attempt to define my entire life trajectory would undermine my inherent sense of how life should be lived. In other words, I prefer to view my life as an ongoing journey, where the road ahead is to some degree cloaked in mystery and thus still uncertain.
This first issue can be partially addressed by being less detailed or precise when describing a hypothetical good life. But even if it is desirable to employ such a tactic to answer this question, the second concern remains.
To the extent that it is possible, I am fundamentally an optimist. So if you propose to me a hypothetical scenario, then I will consider ways to improve upon said scenario. As such, any instance of a (realistic) hypothetical life will ultimately be unsatisfying to me, given sufficient time for contemplation.
For example, while I don't expect to live forever, any pre-specified lifespan is completely unsatisfying due to notions such as longevity escape velocity. One can easily relate this idea to some simple mathematics. Consider, for example, a positive random variable X that follows a folded Cauchy Distribution (a folded version F' of F basically means P(0 < F' < K) = P(|F| < K)). The probability of X taking on larger and larger values shrinks to 0, but its expected value is infinite. This is basically following the idea that the function f(x)=1/(1+x) vanishes as x increases, but its integral over the positive reals is unbounded.
Another way to look at this issue is by considering the two envelopes problem. Conditioned upon knowing a realistic scenario for what might be, I can always imagine something better. Not surprisingly, the solution proposed by Chalmers uses a distribution that has an infinite expected value.
But maybe I'm just weird and severely over-thinking the situation (happens pretty often). Maybe this question is relatively easy for other people to answer.