1-5. Hopefully a few ignores, along with stern self-imposed bans on looking at the posts anyway despite the ignores, will obviate the need for any self-imposed exiles in the future.
I use it mostly as a 'count to 10' type thing. Most of mine are for posters that just rub me the wrong way, and if I'm already in a pissy mood, it'll just set me off. With ignore, I still read many of their posts, but it makes it easier to skip if I'm on a short fuse. The ignore list is more for my own protection -- I don't want to start flaming people.