With respect to the cyclone, I've already downloaded your MPC for the cyclone. (Thanks for posting!) Just have to go grocery shopping for an appropriate plastic bottle...
With respect to a brush, I don't use one on the shoe I created. On an earlier post with images of my shoe, you can see a large channel to the right, which given the spin of the bit is generally where the chips fly (as you are obviously aware based your design). Additionally, with a 0.8" I.D. hose, the abundant volume of air being pulled seems to be more than adequate. That being said, I've only used this style of shoe for ~2 hrs of carves and cutting, so I don't feel that I'm reporting with sufficient experience. There is a very small amount of dust that escapes with the 1/16" carving bit, particularly near the edges of the board. The 1/8" four (4) fluted cutting bit though, when cutting four (4) passes through 13/16" hardwood, spits up shavings through the small hole in the dust cap (probably <2% of the dust), which of course escapes the vacuum.
I have no illusions that I'll be able to get 100% of the dust. My main concern is to limit the amount of dust that collects on the Y and Z belts, and in particular the dust that accumulates around the poorly sealed X gear assembly. Before these last few carves with the dust shoe, I would visit the machine every ~15 minutes, and with a small vacuum attachment, reach in through the top while the carving was underway, and suck up what I could from the mounds of dust building up. I will of course still visit the machine every ~15 minutes during carves, as high speed moving parts and shavings equals a fire hazard, but instead of being on dust patrol, this time I will simply enjoy watching the carving...