Something made me scratch my head

I think it was the hotter spark, especially the coil.
If you had a leakage past the plugs, you would see it.....
It would be obvious.
Compression increase? Minimal. Not enough to make a difference.
NGK plugs are better than champions at any rate.
The electronic ignition, coil, and plugs is where you saw your increase, Mike, in my opinion.
A good tune up and the mods you describe is what gave you the power.
My 2 cents.
Tom.