I'm with you on the comment upvoting. I upvote most of mine with my little vote and have been since I got here. I feel like it helps me get better interaction and generally more post votes. I often ask a question on my posts and get answers, unlike in the rest of my life.
I have certain people who almost always comment at least on one post a day and have become friends with them. Like you, I don't have a lot of time to visit other blogs. I have a list of a few I go to daily and comment on.
I am following almost 4000 steemers and I have never checked my feed in the whole time I have been here!