That's good. What I mean is that you may not even need to bother with that. What is the membership structure you want to create?
You actually have 5 levels, 0 being the free one by default and 1 to 4 paid. Levels give access incrementally.
* A Member with Level 4 access, will also be able to access Levels 0, 1, 2 & 3.
* A Member with Level 3 access, will also be able to access Levels 0, 1 & 2.
* A Member with Level 2 access, will also be able to access Levels 0 & 1.
* A Member with Level 1 access, will also be able to access Level 0.
* A Subscriber with Level 0 access, will ONLY be able to access Level 0.
* WordPress® Subscribers are at Membership Level 0. If you're allowing Open Registration, Subscribers will be at Level 0 ( a Free Subscriber ). WordPress® Administrators, Editors, Authors, and Contributors have Level 4 access, with respect to s2Member. All of their other Roles/Capabilities are left untouched.
You also have availabe what are called Custom Capabilities, which may help you achieve what you want. You can learn about them here:
WP Admin -> s2Member -> API / Scripting -> Custom Capabilitieshttp://www.s2member.com/custom-capabilities-video/And those two can be combined: custom capabilities for grouping and levels for incremental access.
Let me know if that helps.