This depends on what kind of social media sites you are using to post your rants and what kind of followers you are using. If you are short and crips, I think twitter is a better platform. In my opinion, people are not comfortable to long rants, but they will read short pieces. If you want to rant on pinterest and twitter, use pictures to rant as these platforms do not have option for text. Facebook can be more personalized for your rants. But the question is whether your friends are willing to listen or not.