Instead of having a Featured Seller for a whole week, why not one every day? This way everyone would eventually make the front page!
That’s good in theory, but as traffic levels vary enormously from day to day, you might be a bit peeved if you were featured on one day which was low in numbers! One per week is good from the customer’s view because if they are browsing and see something they like and want to go back to it later in the week, then they’ve more chance of finding the shop than if it changed every day.
(Personally, from my traffic levels, I know that some days are very very quiet for me!!)
I think another opportunity for you is to get featured is in the Gift Guides - in this way you’d benefit from being in there for a while, but I do know the search titles have to be good for your items to get picked up, and that’s something I for one need to work harder at!!