If you do plan on removing friends rather than using FB lists and organizing permissions based on lists, I would suggest going to http://www.facebook.com/friends/
It allows you to click X next to each friend rather than going into each individual profile to remove them.
I thought I'd try this out to see how it felt. Using only the criteria "do I care about what this person is doing today?" I managed to axe 122 people, and don't feel bad about it at all.
It allows you to click X next to each friend rather than going into each individual profile to remove them.