I think anyone who is semi social while playing this game and who does a bit of trading has probably come across this issue: An insanely huge friends list that is a mixture of people that include folks ranging form those who added you after one pleasant transaction or random kindness to those who are true friends you speak to daily.
It sometimes becomes very hard to remember and keep track of everyone and it really would help if we could have a second tier added to our friends list to help keep it a little better organized.
The first tier could be something like "friendly acquaintances" and the second could be something like "Friends" or "Buddies."
It's nice to keep track of the people you have run into that were nice, or who traded with you honestly etc. and its a bit rude not to friend them back, so I don't much like the option of just ignoring them and forgetting that we ever met. I really do like to keep a list of the nice folks I have crossed paths with but I think it would be cool to keep it be able to separate them from those folks that are something more to me.