How less prone to swarming do you find the bees on a double brood box system? Is it not harder to deal with than brood and a half or single brood as you have twice the amount of frames to artificially swarm?Why don't you consider double brood as it ensures the bees have enough of their own honey to last them through the long winter months. I didn't need to feed my double brood colonies through the winter and they look as though they're going to come out very strong and very healthy.
As far as I'm concerned brood and a half is the worst of all combinations. The only benefit I can see (other than increased brood space) is that the pollen arch is restricted to the first super with the brood in it.
Unfortunately, when you find queen cells in the super and you want to artificial swarm you get stuck with a "super" sized box.
You don't get the benefit of lifting frames up and down (between brood chambers in a double brood set-up).
With double brood, you normally find them in the top box at the end of winter and you can normally just lift the bottom box out and add a clean box of foundation - so getting good comb change in your methodology.
I know that I'm admittedly pushing my own system, but if you're sure that you want to go either of these two ways instead of single 14x12 or Commercial boxes then I'd strongly opt for double brood.