I don't think you're irrelevant! All of your blogs get more plusses than the average user. I think that you're under appreciated on this site and receive fewer top blogs than other users of your stature because you don't resort to petty drama and nastiness or intense spamming. You're definitely respected and relevant.
But I agree with the random top blog thing; I got a no 1 blog with 1100 points at the height of my irrelevancy! It got more points than I had ever received lol.