The literature calls this broad approach “expansionism” (see also Wilkinson (2021) for similar themes). I’ll note two major problems with it: that it leads to results that are unattractively sensitive to the spatio-temporal distribution of value, and that it fails to rank tons of stuff.
You can reduce the sensitivity to the spatio-temporal distribution of value at the cost of ranking less of the stuff that’s intuitively ambiguous anyway by doing the comparison between two worlds over multiple expansions from a set of possible expansions (e.g. multiple starting points with uniformly expanding spacetime spheres), and using some rule to combine the comparisons that’s impartial with respect to the different expansions. For example, if W1<W2 under at least one expansion and W1>W2 under no expansions (or W1≤W2 under all expansions, which will be transitive as long as the rankings over any fixed expansion is transitive), then W1<W2 overall. Basically, this is Pareto over possible expansions.
You can reduce the sensitivity to the spatio-temporal distribution of value at the cost of ranking less of the stuff that’s intuitively ambiguous anyway by doing the comparison between two worlds over multiple expansions from a set of possible expansions (e.g. multiple starting points with uniformly expanding spacetime spheres), and using some rule to combine the comparisons that’s impartial with respect to the different expansions. For example, if W1<W2 under at least one expansion and W1>W2 under no expansions (or W1≤W2 under all expansions, which will be transitive as long as the rankings over any fixed expansion is transitive), then W1<W2 overall. Basically, this is Pareto over possible expansions.