Your blog and newsletter (oh, please tell me you have both!) are where your fans get to know you as a person and develop the connection which will ensure their fandom for life.
List-growing is all the rage. More more more. Ask these folks “Are you looking for more followers, or better followers?” and they’ll universally say “Both!”
Consider the concept of focus: it’s not possible, with our eyes or our mind, to focus on two things at once. That’s just not what focus means.