Shopify Subscriptions

I'm mostly very happy with the Subscriptions service. A couple of feature improvements I would like to see: 1) the ability to schedule the CC charge date. Currently it recurs on the exact date the customer subscribed. It would be nice to be able to change that date to a specific date so all customers are charged on the same date. 2) the ability to configure the products within the subscription. For example, I run a wine club and would like to allow my customers to switch from Reds to Whites seasonally. Currently, they have to cancel and resubscribe to make that change.