Currently, monthly membership (sbuscription) is $9.99, or $6.99 each if two or more accounts are combined into a family account. Also, 2,500 Crowns cost $5, and 5,000 cost $10.
The proposed idea would allow people to combine both a monthly subscription/membership and Crowns into one Monthly fee. These would be added as additional options and wouldn't replace what's currently there. The option might be called: "Membership and Crowns" or something similar.
Some examples:
$14.99/month: The normal subscription, plus 3,500 Crowns. Note that this would give the subscriber 1,000 more Crowns than if $9.99 was spent on membership and $5 on Crowns. Doing that might encourage some to subscribe to this plan in order to get a few extra Crowns, and it might be enough Crowns for some people in a month. Doing it this way wouldn't discourage those who wanted a better deal by spending $60 for annual membership or $60 for 60,000 Crowns.
$11.99 each/month on a family plan: The normal subscription, plus 3,500 Crowns per account, which could be redistributed as the parent/owner saw fit. This is as above, only with the $3/month discount for grouping accounts into a family.
The idea of this plan is to allow those who may not have the $60/$120 at one time needed for the annual subscription and/or 60,000 Crowns to get a slightly better deal on Crowns than having to purchase them separately, and it also might improve KingsIsle's revenue.