Excluding contexts from a perspective

Use case:

I have a “Mac” context with “Office Mac” and “Home Mac” within it. If a task can be done on either computer, it gets “Mac”, otherwise the specific computer.

At work, I’d like to just show a perspective of tasks I can do. I have a “Home” context, so I can create a perspective that specifically leaves this context out. But for “Mac”, I cannot exclude “Home Mac”. If I just choose “Office Mac,” I don’t get tasks I can do on either Mac. If I choose “Mac”, I get tasks I can do on “Home Mac”.

I realize I can create a third context under “Mac” called “Any Mac”, but this seems like an inelegant solution.

I would like to be able to filter out items in a perspective selection, not just filter in.