USE NEGATIVE SPACE!
If one character is doing the acting - have the other character reacting to it in a less dynamic but still active pose. It's a good trick to use one character's silhouette to frame the other character. The negative shapes between them should be as pleasing in design as their individual positive shapes.This gang of Post kids all have slightly different attitudes and lines of action - which makes them seem organic and alive. Many of today's cartoons just line up the characters next to each other each standing straight up and down, like they have been impaled on the artists' compasses. That's instant death.
Here's Owen Fitzgerald using the same tools as Howie Post - only he is using all the planes of a 3 dimensional space. Howie's poses are very appealing and effective but tend to be balanced on a flat plane.
These poses and atitudes are very subtle and I would say sophisticated. The poses not only do the job of making everything clear and readable, they help tell us who the characters are.
This is very intelligent stuff.
Sorry for doing a whole series about the same 2 artists. I know people like to see variety and something different every day. I was gonna make this all one post, but realized it would be huge and too much to take in all at once.
P.S.
Someone posted a comment in an earlier post that I can't find. he wanted to know if Ub Iwerks cartoons were good to study or were they too "sissified". Tut tut. You should not use a hate word like that. Maybe these pictures will answer your question.