Concept: Allow Pick Lists and Hierarchy Structures to be custom field types.
The reasoning behind Pick Lists (which are menu's that allow you to select multiple items) is that often choices are not Mutually Exclusive. For example, we use custom fields to control which interfaces out KB content should be available too; instead of having 5 yes/no custom fields for each interface, it would be great to have 1 custom field that we could simply check off the interfaces the content should be available too.
The reasoning behind the Hierarchy Structures (similar to products/categories) is to provide more granular detail on selections. For example, if we want to use dispositions as a general concept of what general activity was used to resolve the issue, our product team still wants to know the specific issue that caused the problem; so having a very granular hierarchy selection to further define what bug/issue the incident was related to would be very helpful. A second example - our tickets are escalated often to different departments, but the initial Customer Service person is still 'responsible' for the ticket. We have an 'Owner' field, but it is a single manually controlled drop down menu that gets very long, as it contains all of the names of people who could be 'Ticket Owners'. Being able to replicate the 'Assigned' drop down menu with a 'Group/Staff Account' like structure would make for much better usage.
~Chris