Did a quick forum search. Stunned I found nothing on the topic. And since last time I checked, I'm somewhat sleep-deprived, only slightly mad but definitely not blind (hopefully cough), here it is.
I've unlocked "Sign of the Dreamer" emoticon on Steam. Then it struck me. Bingo.
This, my fellow dreamers, is effectively a cannabis plant. An organic flowerlike prototyped form (TLJ: Dreamfall) that's... grabbing your face? Making you inhale its vapors?
Then a "live" mask-like iteration we see in Chapters, completely covering your face, severing you from the real world by blocking your senses and feeding them generated "dream" content, or, as we can call it by somewhat stretching the truth, externally controlled hallucinogenic experience. It's not exactly "virtual reality" as we know it since while inside a person has full impression of actually being there. The mask itself has no direct connection to plants... if only WATI wouldn't elect a flower-like (or leaf-like) illuminated symbol to be its official logo for the Dreamachine. And brand it on every sample in addition to using in marketing.
I'm convinced the design choice is far from being random. And it is obvious for me that there's more to it than simple drugs and addiction themes (not to say that these topics alone are highly controversial when we talk about cannabis... not unlike Dreaming).
What do you think folks?
And, a question almost as much important. What did Ragnar and RTG wanted to tell us by making the design choice they made?