Thanks for the comments Cirkit! To answer your questions...
> GreenBlaze doesn't have a backstory as of yet. I may think of one soon, but for now I have no idea.
> On Junk King, I have used this shoulder mechanism here, which gives him both support and poseability. Although this shot shows it on another MOC, it's identical on JK apart from it being attached to the Inika Torso used in his frame.
> Those two bots were built before XT4's reveal, but have been modified and tweaked in the time coming up to now.
If you have any more, please don't be afraid to step forward and ask :3
I could show you a shot with the torso armour-less, if that'd help. While I'm at it though, I think I'll post some earlier ones too...
Stormer
PowerKlaw
Rocka
Stormer XL
Minotaur (My personal favourite)
I do also build BIONICLE stuff, but I think HF MOCs are more relevant for EB at the moment.