I think it's a combination and it works out differently for each person. If one wants the most out of steemit, then they should write posts, comment, vote and resteem... some of everything. For most that is unrealistic because of the time that is involved in it. I think people should look at what they enjoy doing the most and at times mix it up.
I always try and post consistently and comment when I can as well as vote. I try and vary it up. I would like to do more with steemit than I currently do.
Yes you are absolutely right. I do the same and enjoy spending some of my time reading posts and commenting :)