You're right, most gets sucked up at the top but if I turn off the bottom portion I get dust in my lap, so some goes that way. And as an added bonus with the larger size most of the small off cuts go into the system with the dust. I get a lot less small pieces on the floor, still some, but less.
Your setup looks like it would work good enough to get most of the dust. I'm just guilty of going overboard most of the time. Lol
Send me your address via private message and I'll send you one of the ones I made if you want to try it.