As long as we're talking about the glass mouthpiece and its silicone (?) holder, take a good look at the holder.
It's got the airholes that feed air from the outside (the holes in the metal mouthpiece) into the chamber. If you look closely you can see that the center of the five holes has a much smaller diameter than the other four holes. Evolv has already tuned the air path so a little less goes to the center of the chamber as opposed to the ends.
So why do I mention this? Many of us (me included) have blocked off the center three holes to increase the draw. I'm assuming that most blocked the holes in the metal cap much the way I did (I used a piece of tape, now on the inside of the cap rather than the outside, and someone else here broke off a toothpick or something in the three center cap holes on each side). Wouldn't it be nice if Evolv made another silicone (?) mouthpiece holder with much smaller holes so everyone could choose their draw strength? It would be much cheaper than retooling the metal cap...
So if you happen to write them about selling the glass pieces by themselves, and you also want a tighter draw, you might mention this too.