Hey sorry, I'm not super familiar with Workshop etiquette but seeing as others were also mentioning this suggestion in the comments I figured that it might be a safe/solid idea to post it here.
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I second the person that mentioned adding an emblem on the arms to at least the Comfy and Crafty styles, since every single one of Engi's shirt area cosmetics retains Engi's yellow emblems on his shoulders (according to the Wiki). That said I actually really really like the Cheery style and would possibly buy one in an instant, I think the yellow on the arms and chest of the Cheery style might be enough to where it wouldn't need emblems on the shoulders. Still though I definitely think all 3 styles could massively benefit from maybe having either a small yellow wrench, or 2 small yellow wrenches in an X crossed position on the shoulders, where Engi's emblem would go, or some design like that. Also I think Comfy and Crafty as they currently are could use some yellow, but if those styles had the yellow wrench design on the shoulders, I think they would look amazing.
Overall this Sweater has so much potential, and I think adding a yellow wrench design to where the emblem goes would really tie it all together and make this one of the greatest sweater cosmetics to ever be added to TF2.