If I won a giveaway where I could pick whatever I want, I would go for one of the most expensive items (which could be a blow to you). If I were you, I would either decide specifically what to giveaway, or maybe giveaway a coupon for a dollar amount off your store. For example, if you gave away a $20 credit, people could use that either for one of your items in full or put it towards a more expensive piece.
Cute illustrations by the way!