I want to display all the latest posts without being locked into a category driven layout
ok this is working now, but I don't like the way it is adding the category because it takes you to another screen which feels like an extra step. I would prefer the post and category entered all on the same screen. In many situations you need to think about the category before or whilst you are writing the post, not afterwards.
I think this is a better workflow perhaps, taken from Discourse, where the category is on a drop down. If you don't select a category it won't let you post.
Or at least for now please change the wording you are currently using to something less wordy
"select a category to post" might be better
We're working on this and very soon it will be out!