I would also like this feature. Our products have different margins, some are very heavy and have lower margins, so we do not want to offer free shipping on those products.
I switched over from woocommerce a few months ago, and I have to say woocommerce’s coupon management was head and shoulders above shopify’s. I could choose whether coupons could be applied with other coupons, use coupons with automatic discounts, and just click which products weren’t available for free shipping.