Saethydd, you asked: Why would a creator with such a high regard for life specifically design a universe in which all life slowly decays?
because slow decay, and also violent ends, provides for screening of desirable outcomes in life's evolution as well as in inanimate mature. example,
generations of stars died, faded away, or compressed in violent collapses, Super Novae.
both types of death have produced all the abundant element we need, all made from Hydrogen.
Dying is good for us, as a whole. possibly done without the creator lifting so much of a finger, after the creation event.
not speaking for the wt/bible god here, but a possible creator, defined only as observed by the action of his creation.