Perhaps not the least controversial idea here, but ...
... everyone who loves the PCMark05 benchmark because of all the tweaking should consider making the tweaks public. When everyone knows the tweaks, people get interested again and will start benching again. Now, with undisclosed tweaks, a first attempt is like 75% lower than the top score. And because all this tweaking requires quite a bit of software knowhow it's very discouraging.