He's looking great Gerry.
I'm curious and not sure if you've already stated your plan with regard to his hair.
Do you plan to use helmet hair?
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I'm wondering if I'm creating problems for myself later with these shoulder bags, in terms of rigging and secondary movement, etc. He never really uses them, they're more part of his "look", and maybe they'll ending up being too much trouble later. What do you think?
I have two thoughts here.
1. He's gotta be wearing something.
2. It seems to work for this character.
Beyond that I would perhaps look at some real life actor/models that might be wearing something similar to see how you might adjust it to meet your purposes. I think it does add some interesting detail and helps to frame his body and direct attention to his head.
From a design view:
If you were to look at each of the main characters from the standpoint of extremely basic shapes do these shoulder bags distinguish him from the others easily. This will help when the characters are seen at a distance.
Also, from a purely practical or personal vantage point... Why is Colfax wearing the shoulder bags?
Where did he get them?
Does he ever wear anything else?
Do they serve any other purpose in the story?
Do they keep him warm in the cold and cool in hot weather?
Who made them?
Is it something others with a similar background might be wearing?
Does he have similar clothes that he wears?
Will he always be wearing this? (For the longer story I'd say this is not recommended. In the over all scheme of things consider three main ensembles for him to wear. Can you plot the critical moments where he will be wearing this?)
Can you move from this outfit to one more simple and one more detailed easily (assuming this to be the main outfit he will wear)?
For instance, I can see him taking this off in very informal situations revealing a tight shirt underneath and completely setting it aside for occasions requiring more formal wear.
Animation-wise... as Nancy suggests.. just keep it simple. Consider adding details via decals, etc.