Hi George!
First, just let me pump your ego a bit (I'm sure you don't need or want that, but it always feels good lol). I just took a looksie at the first page of your topic, and I must say you should be proud of the leaps you've taken on your work! Keep working hard! Or smart! or both!
Now, before your head grows to unmanageable proportions, the crits :P
On the Big Arm guy, I really think you should revise his pose before going any further. He is giving me mixed signals as he is now: An arm like that on that body, suggests a very unbalanced individual, a freak. The pose suggests a more formal, sane person. So the viewer can't decide about what that character is all about.
As for this last character, he will be sweet. I think he deserves a large, open mouth, with lots of teeth :D
You could exagerate the "S" shape of his body though.
Hope that helps!