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The research and details are what makes this pursuit interesting for me. Usual reviews tend not to cover these things (one of the reasons I enjoy the work of John Siracusa).
I would be extremely interested in a list of the things you have found to be best for you, and the reasons you came to that decision, or the process by which you arrived there.
This was a great exercise as it's something you can do as you walk about, or in your case, you can apply it to websites in much the same way. It gets you in the right frame of mind. By constantly being on the lookout, it starts to become ingrained, and you can start to identify fonts automatically. You judge what you like and dislike and what you would change to achieve a desired effect.
As with many things, critical constructive thinking is the key. And perseverance.