When you click "Edit Subscriptions" on the Overview page, the slider becomes live and you can automatically subscribe to journals, in order of cost-effectiveness. What does this mean in detail?
What we've done is ordered all of the journals in your scenario by a cost-effectiveness metric called Net Cost Per Paid Use (NCPPU). Read more about NCPPU here -- it is like the well established Cost Per Use metric, but also includes citations and authorships as a type of usage, excludes articles that are available for free (through your perpetual access, open access, or academic social networks like ResearchGate), and accounts for the cost of ILL should you not subscribe.
When you move the slider, we automatically subscribe you to journals with the lowest NCPPU first, and subscribe you to as many journals as we can, in order of increasing NCPPU, such that the total cost of subscriptions for journals you've subscribed to plus the total cost of ILL of journals you haven't subscribed to is less than the dollar amount you've specified by the slider.
If you decide to "save subscriptions" in your scenario, you can then navigate to the Journals tab and see the subscription status of individual journals, the subscription cost, the ILL cost, the NCPPU, the usage, and all other details.