Ask HN: What's your email tags structure?

I was wondering what's the preferred way of organizing tags for emails and what fellow IT-related people are using as a strategy to do this.

I personally am using my personal email address also for work ( I'm a freelancer ) and I'm using gmail as a host and Airmail as MUA.

My current organization is similar to :

    - family
    - friends
    - domains
    - logs
    - payments
      - paypal
      - bank
      - ...
    - projects
      - ...
    - purchases #Keep track of what I expect to be delivered 
    - social
      - stackexchange
      - facebook
      - twitter
      - ...
    - subscriptions # Any newsletters 
      - ...
    - travel # Keep track of my airplane tickets
      - BER -> SOF - Sep '14
      - BER -> AMS - Oct '14
      - ...
    - work
      - freelancing
      - job offers

I think mine is a little bloated. I use a lot of filters, but seems to be hard to manipulate all efficiently. My inbox is a lot behind inbox zero concept.

Anyway what works best for you? Any tips?