As far as the off hand cycling, there is going to be a power factor with the handguns and with a service load in a .45 single action, the recoil will roll the gun up and give little to no advantage anyway.
Some people fire one handed because it is traditional and a two handed shooter fires in the same class. Can't do away with two handed shooting as the older or disabled gents might really need to use two hands.
The rules are all very well thought out, considering all the factors involved and trying to keep things level.
I collect US Military, but there are some foreign guns that stand out.
This is my Broom Handled Mauser with holster stock. Just had to have one because it was cool and one of the few shoulder stocked handguns legal to own without special paperwork.
These are legal in GAF, without the stock attached. The trick is getting it to work with lead bullets! I haven't tried and these things are awkward to shoot without the stock anyway.