I see what you're saying, but I think that just means you're not following the right people. I have conversations all the time on twitter, and that's really how I've developed a following. I've gotten multiple music gigs and have even found friends through twitter. It's actually amazing the conversations you can have! Try unfollowing the people who only retweet others and find some more people who tweet generally tweet interesting things. I think you'll find it a lot more enjoyable!