I think it doesn't really matter. I also followed only people I was genuinely interested in. But those people are also interested in many other things (naturally) that are less interesting to me. Plus there are all these re-steems, posted by yet others, that leave me completely cold. Among all these posts the real interesting stuff gets buried deeper and deeper. I guess one thing you could do is actually follow a person, that is looking up their profile page periodically. That's what I've started doing. Though in the meantime there are new followers and interesting people to follow....