[Speedslug]

OK.

I was just thinking that the flex right over the troches could be replaced with some of those 4 section 90 degree bends.
I have one on the tail end of my system twisted corkscrew style into about a 20 degree angle.
Any place you can reduce the turbulence will up the volume and increase efficiency.

Happy melting.

ETA: Aye, I remember going through that website some half dozen years ago.
My main concerns are about the stated rating of the fan you are using and the classical marketing method of setting up testing practices to with the absolute best possible conditions so the numbers come out smelling like roses but when the same equipment is placed in real world conditions the values drop to 10% of the advertised specs.

I also remember an LE member with industrial hygiene credentials named Dale (I think) and a few others stating that for a barley box or hood arrangement you want a minimum of 125 cfm per square foot of the open face of the work area.

I see ventilation as a classic case of more is better and I myself would not be comfortable unless I had twice or three times what you are working with here.
But I wont belabor the point.

Enjoy.