I tried to learn about these things when I was setting up dust collection for my wood shop - same problems, pretty much. There is something called "capture velocity," which I think is when the energy of the air overcomes the energy of the moving particle itself. Of course smoke particles are much smaller than wood, but still...
When I ponder fume extraction, it seems like it works inefficiently because the air velocity falls off so rapidly as we move away from the vacuum inlet. We go from, say, the cross-section of a 100mm tube to a cross-section of the open space, meters, and the velocity is reduced by that ratio. Thus... "has to be very close."
So it seems to me the way to make it work would be push-pull, where you can have a directional small-diameter flow across the work area, and then have a receiving vacuum inlet on the other side. If the receiver is large enough to cover the expanded air stream, the capture happens at the surface of the inlet, where the intake velocity is still high.
And when I say "vacuum", I mean something like a fan pulling air through a tube. And the gentle air source doesn't need to produce hurricane winds, either. Anyway... just some thoughts. A couple fans, some tubing, a HEPA filter. Maybe only one fan, in a loop.