Another good development path is to write Wikipedia articles. You get to see someone "kill your darlings" and perhaps learn from it. Plenty of readers too. But there is no opportunity for blog-like self promotion. You only get better writing and analyzing skills.
Editing popular articles vs. starting a new one are completely different experiences.
The only downside to this is that typically, there's little promotion angle here.
I have no idea who wrote/contributed to the vast majority of the many wikipedia links I reference in comments and emails.
It does bode well for resume-padding however - you can just link to your body of contributions and some stats (edited 1k articles, etc). As a hiring manager/customer, that'd definitely pique my interest.
