Multiple lists of modules:
It would be very useful to be able to create multiple lists. This helps when reorganizing your system, keeping an overview of a wishlist, and perhaps grouping modules for particular activities (e.g. 'on-the-road modules', 'live jam modules', 'fieldrecording set', etc).

At the minimum being able to separate the modules that you have from those that are on the wishlist would already be great. And also: 'modules-I-own-that-are-currently-in-my-system' and 'modules-I-own-that-arent'