I like elements of all three of the example rubrics but I find the detail of the second rubric most helpful. While not as visually appealing and straightforward as the third rubric , I appreciate the breakdown and how the most important sections (Content/Creativity, Voice, and Text Layout) are weighted more heavily than citations and quality of writing. Though there is still a necessity to fulfill these categorical requirements, I think being less weighted speaks to the fact that many blogs have a more informal style and flow. This doesn’t mean citations and grammar should be ignored, but there seems to be more leeway here than, say, in an academic paper or article.
In this case I don’t think I’d change much of anything. Maybe, instead of using percentages for each section, I would use the 1-4 Likert-type scale used by the other two rubric examples. From a facilitator’s perspective (depending on how many blogs are being reviewed each week) using this scale might speed up the evaluation process a bit.