I think they will make great improvements! Epic always does in my opinion. I think a notification system through the marketplace would be great. For example, let the seller know when comments or questions are made on the product page, also a favorites page I agree with that, to check progress on the products and refer to for anything else. As well as notifications to customers or consumers about when the seller upgrades to new unreal engine version. So in short better communication and a reference page 
Those to me would be the greatest improvements I think.