Bring the security group field onto the contracts form so that it is easy to see which security group each contract belongs to.
Make it more simple to change whether a particular security group has read only or full access.
Ability to change the name of the field "security group" so it can be something more meaningful to each customer. For example, if security groups are driven by business units then the security group field can be renamed "Business Unit" and each specific security group can then be a particular business unit. This will allow security groups to be more meaningful to each customer as well as reduce the number of fields by one (by combining security with a field that already has meaning rather than have 2 separate fields)
The ability to rename the default security group from "Everyone" to whatever makes sense for each customer. So, for example, if security groups are driven by business units, the default "everyone" group might be "Corporate Group"
Improvements to the way the multiple selects work when choosing one or more security groups
The more complex features that control "pass-down" security groups will remain in the security group field accessible on each contract if these features are required