After a time passes, I push lets say E10 and I see A10 logged (and acted on) instead...
That's a peculiar one. E10 on would send 2 commands (E10, E ON) and should not have anything to do with HC A. If it's turning A modules on when sending an on command for an E HC module, that certainly seems to be a bug. I use HC A primarily with a few specific modules on B, C, E, and O. All lighting is on HC A. If HG was reporting that it sent E10 on, then I'd suspect some kind of signal corruption, however, that would be a strange corruption to see regularly.
HC A = b0110 or h6
HC E = b0001 or h1
I've heard that some people have issues with device M13 (HC = b0000, UC = b0000) since noise on the power line can apparently look like this module, but it seems odd that you would see this on E10/A10 regularly.
As for All ON/All OFF, no I don't use it.