Thanks for such a comprehensive and thoughtful response Cyangmou. m(_ _)m
Indeed, I didn't really do any animation planning before I started drawing so the animation suffers from basic construction issues.
Overall with the flour sack, I'm trying to break away from being precious about the silhouette, and to push the squash and stretch in the movement as far as possible. When I animate I naturally err on the subtle side, so if I do planning that's too far, I find it easier to make it more lively.
The flour sack's squash does pop, since it has too few frames, but I like the motion, for blocking stage. The up/down is a lot better and it feels less like cardboard.
For now I'm keeping it in flats and as few frames as possible to make it easy to correct. For example, the tail's going to take a lot less time to correct when there's only six frames! Once I've got the motion in a better place I can noodle. For the final animation I'll probably err more towards double what I've got now, maybe a bit more if I want to ease.
For this revision, I've added in a pass pose:
The blue is just a WIP thing, it'll go back to orange next update.
Though it's kinda hard to see on a light bg, hm.
Edit 8/20:
Here's the next version:
Next to the blue one, to make it easy to compare. Went through and separated into layers to make editing easier.
Added in some follow through on the ears, not sure if it's too much.
Once I work out the tail, I'm thinking about working on the first background.
Cracked open Richard Williams and thought about wave action:
I'll work on the tail tomorrow.