There were three problems I realized from the original...
1. I found it less natural for squirrels, specifically redwall squirrels to be on the ground. It didn't portrayed their character as much as I intended to, so I re-illustrated him on his natural environment.
2. His costume from the original looks like a incoherent mash up of random clothing. Other than that, squirrels are commonly portrayed as scouts and archers.
3. Most people remember Rakkety Tam from the original illustration. It's not supposed to be that way. Rather, the illustration should represent the race in general.