Here are my thoughts thus far on the example I posted a few days back.
Let's say that our intuitions are strong that we are to save the 2 year old child.
I think that a case can be made that there is a greater qualitative value to conscious life (defined appropriately to include sleeping individuals and such) over 'bare' human life.
The example could shift so as to have enough organisms at the early stages of life to outweigh the consciousness advantage of the 2 year old, but in such a scenario it is no longer clear that our intuitions are as clear cut.
Does this mean that one ought to save a 2 year old child instead of 5 coma patients? It depends on how we describe the coma patients and how we describe the early stage organisms. I think the issue hinges on how likely conscious life is to result from either set of organisms (perhaps this is part of our intuitions in the original case since few very early stage organisms actually make it to conscious life). If we stipulate that more than one of the organisms in either group is guaranteed to make it to consciousness, then we should save the group (once again the group could be inflated to make this guarentee, but then I think the intuition to save the child would dramatically weaken if not disappear).
Another alternative is to make the difference between the child and the early stage organisms a difference in kind not degree. This approach fits the idea that those organisms have (only) the potential for human life. This approach might be better, but it is at least more complicated.
An argument against this kind of view can be found here. I am not yet sure of its merits.
A good positive argument that I found is here.