Professional blogs generate a torrential flow compared to personal blogs. In a river of posts where all sources are competing for attention, the professional posts flood out the personal ones. Your reader needs a rate limiter for overposters.
RSS readers need to make it trivial to reply to your friend, with similar gestures to Facebook and Twitter. It should be possible to post a private reply, to Like, to repost/retweet, or to comment in-place in your reader. The software should have sophistication comparable to Facebook, for example there should be a range of Like types that include “wow” and sympathy.
RSS readers also need to provide readership metrics to publishers. Otherwise your friends with personal blogs get close to zero feedback. With a big professional-scale blog there are enough readers for comments to happen. But with a personal-scale blog comments are few and far between.