The search for gravity waves is not futile, just misdirected by the lack of a principle of unification. I like to call them matter waves since gravity and quantum forces are really just versions of each other. Matter is the constant and gravity is simply a scaling of charge force.
The CMB is not a remnant of the big bang, but rather simply a manifestation of a shrinking and not expanding universe. It is not clear to me why this is not clear to everyone else, but that is life.
The energy conservation law works for quantum as well as classical, but needs to allow for interference effects and phase coherence. On the scale of the universe, interference effects can be quite significant.
The LIGO experiment will need to be retuned in order to detect matter waves because electromagnetic effects in some sense parallel gravity effects with interfeometers.