If the stock draw is 10amps, but I’m running all LED lighting, is it a fair assumption that the overall draw would be around 7-8 amps?
Nope. Assumption predicated on facts not in evidence.
Can calculate the wattage of the bulbs you replaced. Then compare to the watts used by what's now installed. Anything else is just a W.A.G.
The increased risk to the field coil is related to how hard you are making it work on some production examples of the coil. If you always have a consumption margin of 2 amps while revving, it should be okay so long as your idle time is about 1/4 or less of your riding time. Expect to use a battery maintainer while parked.
I’ve got a Hondaman ignition I’ve yet find time to install, and was going to do it at the same time as the grips… Which also draws less than stock points, ya?
No. Adding a power consuming device does not draw less power than the stock points. I'm baffled at how could you arrive at that concept? Electronics is highly math oriented. And 2+1 never = less than 3 in the universe we all live within currently.
Unless you start measuring, rather than trying to argue/theoreticise your way to condescension, nothing's going to be resolved. I expect you'll just do what you want to, irregardless of facts.
I'd go with gloves (and did so for years without being heated) in 40 degree weather at 70 MPH in daily commutes in the south bay. Gloves are also safety equipment much needed in a let off. But, will probably clash with the sneakers desired for stylish riding. :-)
Cheers and best of luck,