I never understood why the position of the saddle's nose was a reference point. The relevant reference point on the saddle is where one rides - that is, where one's sitbones or pubic bone fall. A bone can be placed at varying distances from the nose, but the bone will fall approximately the same distance from a fixed reference point if the bike is set up to the rider's preference.
I also don't understand the focus on COG as determined by ability to ride no-hands without falling over. I've got greater core strength now than a year ago and in October of 2020, at the end of last year's riding season. With luck, good health, and a good bit of riding, my core strength will be higher in October of 2021. I can lean over farther now than a year ago. In 4 months, with good health and a good bit of riding, I'll be able lean over still farther without falling. My COG changes, and I imagine everyone's does.
Bike fit captures a moment in time, doesn't it? But life is change and adaptation.
If you're worried about power, my reco is to get a power meter. If you can't afford a power meter - it wouldn't fit into my budget at this point - I recommend riding more, monitoring what you can monitor, and aiming to improve what you can measure until your budget can include a power meter.