I just went through this with Workfront Support and they suggested I add this to the ideas exchange as others may have the same thought.
If you go to Statuses, Issues are the only item that you can have more than one set of statuses for (i.e. issue types). However, for our purposes, we have different types of projects: Some projects have custom statuses that are different than other projects. The workaround is to assign statuses by group, but ideally, you would have the ability to select a custom status for projects the same way you can for Issues.