Okay, you would literally see a direct increase in profit if you allowed cosmetics to apply to kits and put some kind of cosmetic in that applies to the hobo sacks. Engineer players would be more likely to spend ridiculous amounts of money in the gem store buying cosmetics and converting gems to gold, like other professions, if cosmetics item applied to them fully. For example, the new jet pack from MF would fit an engineer perfectly, but why would I bother since I’ll be displaying a hobo sack 70% of the time anyway.
So, to sum it up, you will make money if you fix this. Do it.