Blogs are basically a reward for being a productive, friendly, and non-abrasive member of the community, be it through donating to help Rukario pay for the server (supportership method - I think you have to be at least Tier 2, maybe Tier 3 for it), posting productively and contributing to quality discussions and not flaming anyone and reporting posts using the reports system instead of minimodding (this is for the 5000 posts method as well as the moderator method). Becoming a moderator is definitely the hardest path to getting a blog since you have to be a mature, responsible, non-abrasive (meaning don't be a jerk to anyone), rule-abiding, difference-respecting, and active member (there's probably a few other standards I'm forgetting) who reports posts for one of the moderators to deal with instead of telling the offending poster yourself.