I enjoy connecting with like-minded people and with those who are different, interesting, and generally civil. For lists of my interest, see my tag list and/or profile. Be aware that my interests are extremely diverse and my audience likewise.
I use venue friending tools primarily:
* to manage privacy
* to read blogs/posts that I like
* to save typing if the program fills in listed friends when sending messages.
I do not use it as an analog of social affection, so if that's how you use it, expect mismatches to occur.
I typically friend blogs that are active, have things I want to read, and are mostly or entirely public. I rarely friend blogs that are mostly or entirely private, because the lock dingbat is so small I miss it. Therefore, the most effective way to avoid annoying everyone by linking to locked posts is to avoid reading blogs that lock posts. I myself almost never use the lock function, because once something goes into electronic form it is no longer private. Things I don't want people to see, I usually don't post. Most of my posts are available for everyone to see and comment, but when spam surges occur, I do things like turn off anonymous comments and switch down to logged in users or friends only for a while. Consequently, I don't really use the "grant access" function either.
I rarely use these things for social grooming either. I do that with posts, links, and comments. I am an enthusiastic signal-booster with a lively audience that occasionally stampedes over to look at whatever I am pointing to. If that isn't something you like, this probably isn't the blog for you.
Therefore, I don't automatically add people back if I see they have added me. I do check the blog to see if it fits my parameters. By all means, drop me a comment or message when you subscribe to my blog if you wish, especially if you want to mention how you found me and/or what we have in common, but it's not required.
I interact freely in communities, in my blog, and in other blogs. I don't mind if people get into long conversations in comments under a post. (If it goes far off topic, you may want to open a new post in your blog and link to that from my comment thread.) I comment whenever I feel like it, and am chatty. I'm also differently civilized, which makes me a poor match for the mainstream, and a very good match for a number of less-advantaged cultures. I suggest that people browse my blog before subscribing to it.