In several stories regarding the Insecticons' nature and origins, the concept of "mutation" is often brought up. In IDW, the Insecticon Trio are the mutants; the odds of producing them were a 1000:1. In other continuities, the Big Three are the original Insecticons with the others being progressively-inferior clones. Whichever the case, mutation requires genetics of some sort, a baseline to make changes from. To paraphrase a Transformer-related article from "Popular Science" magazine, Transformers exhibit physical and behavioral diversity that's more akin to biological reproduction than simple construction. This is a field called evolutionary robotics. Instead of simply building a robot, the computer randomizes genetic algorithms within a set parameter to determine the robot's design. Simply put, it introduces diversity and mutation to the Transformer "gene pool". Why are some bots bigger; how can this one teleport while others can't? It's chance; chance and resources. It's a reasonable explanation as any, and would definitely explain why Transformer physiology is so consistent despite their varied forms. I believe that, more than other Cybertronians, Insecticons would be affected by this. Some of their traits are more analogous to organic life than mechanical, and this would be no exception. This, their diversified palette (G1 states they can consume both organic and non-organic material), beast-modes, universal repulsiveness on both sides and connections with Airachnid/Blackarachnia all lead my to assume that the Insecticons are techno-organic. A bit anti-climatic, isn't it? But hey, it's my first post.
I do think that the Transformers in general are sort-of techno organic (they have their own equivalent if DNA after all), but I wouldn't single out the Insecticons just because they can clone themselves and eat trees. In the cartoons the Decepticons could make energon cubes from practically anything (there's a scene in episode two where they are making energon in the middle of a forest). Do the G1 transformers have parts and programs analogous to stuff we'd find in evolved organic life forms? Sure. Do they have organic parts? Well, aside from the binary-bonded guys, I'd say no.
Of course not. Very few Transformers in G1 had any organic pieces, like you said. Forgive me if I gave an impression suggesting otherwise. I simply believe that in the newer continuities, it would make sense for them to be techno-organic.
Also keep in mind that the original three were G1 transformers that took insect forms....when they created more copies of them self they made a fixed # due to resources and time. But also if they are making copies of themselves ...eventually as they use up their energon supplies....the resulting clones will definitely be inferior in quality and strength compared to the original insecticon. look at it as when a copier first stars out....excellent and sharp copies of the original document.....but as the toner gets low....you start to get crappy copies of the original made. That's the way the G1 insecticons reproduced to me when watching the cartoon . Can't make an opinion on the IDW story since i have never read it.